diff --git a/litellm/caching/evicted_client_closer.py b/litellm/caching/evicted_client_closer.py
index 555f6a25324..862f9ddb82e 100644
--- a/litellm/caching/evicted_client_closer.py
+++ b/litellm/caching/evicted_client_closer.py
@@ -29,6 +29,9 @@ it does not belong to. Queued clients are therefore bucketed by what it takes to
 close them, and each bucket is ordered by deadline, so a reap walks the entries
 that are due rather than the whole queue.
 
+A bucket whose loop has been collected is dropped, and its clients are left to the
+collector, as they are when the queue is full.
+
 The queue holds its clients weakly, so waiting out a grace window never keeps
 alive anything the collector would have reclaimed first.
 """
@@ -36,6 +39,7 @@ alive anything the collector would have reclaimed first.
 import asyncio
 import contextlib
 import inspect
+import itertools
 import threading
 import time
 import weakref
@@ -55,6 +59,9 @@ _CLOSABLE_ANYWHERE: Final = "closable-anywhere"
 _CLOSABLE_ON_ANY_LOOP: Final = "closable-on-any-loop"
 
 _BucketKey = str | int
+_LOOP_TOKENS: Final[weakref.WeakKeyDictionary[asyncio.AbstractEventLoop, int]] = weakref.WeakKeyDictionary()
+_LOOP_TOKEN_COUNTER: Final = itertools.count()
+_LOOP_TOKEN_LOCK: Final = threading.Lock()
 
 
 @dataclass(frozen=True, slots=True)
@@ -65,12 +72,12 @@ class _PendingClose:
     collector would otherwise have reclaimed first.
 
     ``needs_loop`` is set for a client whose close is a coroutine; those can only
-    be closed from the event loop they were evicted on, recorded in ``loop_id``.
+    be closed from the event loop they were evicted on, recorded in ``loop_token``.
     A client that closes synchronously carries neither constraint.
     """
 
     client_ref: "weakref.ref[object]"
-    loop_id: int | None
+    loop_token: int | None
     needs_loop: bool
     close_after: float
 
@@ -79,16 +86,24 @@ def _bucket_key(pending: _PendingClose) -> _BucketKey:
     """Which reaps can close this entry: any at all, any running a loop, or one loop's."""
     if not pending.needs_loop:
         return _CLOSABLE_ANYWHERE
-    if pending.loop_id is None:
+    if pending.loop_token is None:
         return _CLOSABLE_ON_ANY_LOOP
-    return pending.loop_id
+    return pending.loop_token
 
 
-def _running_loop_id() -> int | None:
+def running_loop_token() -> int | None:
     try:
-        return id(asyncio.get_running_loop())
+        loop: Final = asyncio.get_running_loop()
     except RuntimeError:
         return None
+    try:
+        token: Final[int | None] = _LOOP_TOKENS.get(loop)
+        if token is not None:
+            return token
+        with _LOOP_TOKEN_LOCK:
+            return _LOOP_TOKENS.setdefault(loop, next(_LOOP_TOKEN_COUNTER))
+    except TypeError:
+        return id(loop)
 
 
 def _close_function(client: object) -> Callable[[], object] | None:
@@ -186,6 +201,8 @@ class EvictedClientCloser:
         self._clock = clock
         self._owned: weakref.WeakSet[object] = weakref.WeakSet()
         self._buckets: dict[_BucketKey, deque[_PendingClose]] = {}  # mutable-ok: deadline-ordered queues
+        self._dead_loop_tokens: deque[int] = deque()  # mutable-ok: loop finalizers append without taking the queue lock
+        self._watched_loop_tokens: set[int] = set()  # mutable-ok: tracks tokens until their dead buckets are discarded
         self._pending_count = 0
         self._queue_lock = threading.Lock()  # the cache is reachable from every worker thread's loop
         self._close_tasks: set[asyncio.Task[None]] = set()  # mutable-ok: strong refs to running closes
@@ -216,13 +233,19 @@ class EvictedClientCloser:
         close_fn: Final = _close_function(client)
         if close_fn is None:
             return
+        loop_token: Final = running_loop_token()
+        needs_loop: Final = inspect.iscoroutinefunction(close_fn)
         if self._pending_count >= self._max_pending:
-            return
+            self._discard_dead_loops()
+            if self._pending_count >= self._max_pending:
+                return
+        if needs_loop and loop_token is not None:
+            self._watch_loop(loop_token)
         self._enqueue(
             _PendingClose(
                 client_ref=weakref.ref(client),
-                loop_id=_running_loop_id(),
-                needs_loop=inspect.iscoroutinefunction(close_fn),
+                loop_token=loop_token,
+                needs_loop=needs_loop,
                 close_after=self._clock() + self._grace_seconds,
             )
         )
@@ -236,7 +259,7 @@ class EvictedClientCloser:
         if not self._pending_count:
             return
         now: Final = self._clock()
-        for pending in self._take_due(_running_loop_id(), now):
+        for pending in self._take_due(running_loop_token(), now):
             client = pending.client_ref()
             if client is None:
                 continue
@@ -249,6 +272,29 @@ class EvictedClientCloser:
     def pending_count(self) -> int:
         return self._pending_count
 
+    def _watch_loop(self, loop_token: int) -> None:
+        if loop_token in self._watched_loop_tokens:
+            return
+        try:
+            weakref.finalize(asyncio.get_running_loop(), self._dead_loop_tokens.append, loop_token)
+        except TypeError:
+            return
+        self._watched_loop_tokens.add(loop_token)
+
+    def _discard_dead_loops(self) -> None:
+        with self._queue_lock:
+            self._discard_dead_loops_locked()
+
+    def _discard_dead_loops_locked(self) -> None:
+        while self._dead_loop_tokens:
+            self._discard_dead_loop_token_locked(self._dead_loop_tokens.popleft())
+
+    def _discard_dead_loop_token_locked(self, loop_token: int) -> None:
+        self._watched_loop_tokens.discard(loop_token)
+        bucket: Final = self._buckets.pop(loop_token, None)
+        if bucket is not None:
+            self._pending_count -= len(bucket)
+
     def _enqueue(self, pending: _PendingClose) -> None:
         """Append to the entry's bucket, dropping any dead entries it queues behind.
 
@@ -257,6 +303,7 @@ class EvictedClientCloser:
         the front rather than having to be searched for.
         """
         with self._queue_lock:
+            self._discard_dead_loops_locked()
             bucket: Final = self._buckets.setdefault(_bucket_key(pending), deque())
             while bucket and bucket[0].client_ref() is None:
                 bucket.popleft()
@@ -264,9 +311,12 @@ class EvictedClientCloser:
             bucket.append(pending)
             self._pending_count += 1
 
-    def _take_due(self, loop_id: int | None, now: float) -> tuple[_PendingClose, ...]:
-        buckets = (_CLOSABLE_ANYWHERE,) if loop_id is None else (_CLOSABLE_ANYWHERE, _CLOSABLE_ON_ANY_LOOP, loop_id)
+    def _take_due(self, loop_token: int | None, now: float) -> tuple[_PendingClose, ...]:
+        buckets = (
+            (_CLOSABLE_ANYWHERE,) if loop_token is None else (_CLOSABLE_ANYWHERE, _CLOSABLE_ON_ANY_LOOP, loop_token)
+        )
         with self._queue_lock:
+            self._discard_dead_loops_locked()
             return tuple(pending for key in buckets for pending in self._drain_locked(key, now))
 
     def _drain_locked(self, key: _BucketKey, now: float) -> Iterator[_PendingClose]:
diff --git a/litellm/caching/llm_caching_handler.py b/litellm/caching/llm_caching_handler.py
index a89e43b78b4..ccc4b314e44 100644
--- a/litellm/caching/llm_caching_handler.py
+++ b/litellm/caching/llm_caching_handler.py
@@ -2,10 +2,9 @@
 Add the event loop to the cache key, to prevent event loop closed errors.
 """
 
-import asyncio
 from typing import Final
 
-from .evicted_client_closer import EvictedClientCloser, default_evicted_client_closer
+from .evicted_client_closer import EvictedClientCloser, default_evicted_client_closer, running_loop_token
 from .in_memory_cache import InMemoryCache
 
 
@@ -43,24 +42,22 @@ class LLMClientCache(InMemoryCache):
         self.evicted_client_closer.schedule(evicted)
         self.evicted_client_closer.reap()
 
-    def update_cache_key_with_event_loop(self, key):
+    def update_cache_key_with_event_loop(self, key: str) -> str:
         """
         Add the event loop to the cache key, to prevent event loop closed errors.
         If none, use the key as is.
         """
-        try:
-            event_loop: Final = asyncio.get_running_loop()
-            stringified_event_loop: Final = str(id(event_loop))
-            return f"{key}-{stringified_event_loop}"
-        except RuntimeError:  # handle no current running event loop
-            return key
+        token: Final = running_loop_token()
+        return f"{key}-{token}" if token is not None else key
 
-    def set_cache(self, key: str, value: object, litellm_owned_client: bool = False, **kwargs):
+    def _scoped_key(self, key: str, loop_bound: bool) -> str:
+        return self.update_cache_key_with_event_loop(key) if loop_bound else key
+
+    def set_cache(self, key: str, value: object, litellm_owned_client: bool = False, loop_bound: bool = True, **kwargs):
         """``litellm_owned_client`` marks a client litellm built, so it may be closed once evicted."""
         if litellm_owned_client:
             self.evicted_client_closer.mark_owned(value)
-        key = self.update_cache_key_with_event_loop(key)
-        return super().set_cache(key, value, **kwargs)
+        return super().set_cache(self._scoped_key(key, loop_bound), value, **kwargs)
 
     async def async_set_cache(self, key: str, value: object, litellm_owned_client: bool = False, **kwargs):
         if litellm_owned_client:
@@ -68,13 +65,13 @@ class LLMClientCache(InMemoryCache):
         key = self.update_cache_key_with_event_loop(key)
         return await super().async_set_cache(key, value, **kwargs)
 
-    def get_cache(self, key, **kwargs):
-        key = self.update_cache_key_with_event_loop(key)
+    def get_cache(self, key: str, loop_bound: bool = True, **kwargs):
+        scoped_key: Final = self._scoped_key(key, loop_bound)
         self.evicted_client_closer.reap()
 
-        return super().get_cache(key, **kwargs)
+        return super().get_cache(scoped_key, **kwargs)
 
-    async def async_get_cache(self, key, **kwargs):
+    async def async_get_cache(self, key: str, **kwargs):
         key = self.update_cache_key_with_event_loop(key)
 
         return await super().async_get_cache(key, **kwargs)
diff --git a/litellm/integrations/agentops/agentops.py b/litellm/integrations/agentops/agentops.py
index 3364520a8ae..3666cd88a9d 100644
--- a/litellm/integrations/agentops/agentops.py
+++ b/litellm/integrations/agentops/agentops.py
@@ -102,18 +102,14 @@ class AgentOps(OpenTelemetry):
             "Connection": "keep-alive",
         }
 
-        client: Final = get_httpx_client()
-        try:
-            response: Final = client.post(
-                url=auth_endpoint,
-                headers=headers,
-                json={"api_key": api_key},
-                timeout=10,
-            )
+        response: Final = get_httpx_client().post(
+            url=auth_endpoint,
+            headers=headers,
+            json={"api_key": api_key},
+            timeout=10,
+        )
 
-            if response.status_code != 200:
-                raise Exception(f"Failed to fetch auth token: {response.text}")
+        if response.status_code != 200:
+            raise Exception(f"Failed to fetch auth token: {response.text}")
 
-            return _DECODED_JSON.validate_python(response.json())
-        finally:
-            client.close()
+        return _DECODED_JSON.validate_python(response.json())
diff --git a/litellm/llms/custom_httpx/http_handler.py b/litellm/llms/custom_httpx/http_handler.py
index a8be217709f..5620971a8a2 100644
--- a/litellm/llms/custom_httpx/http_handler.py
+++ b/litellm/llms/custom_httpx/http_handler.py
@@ -1205,6 +1205,17 @@ class AsyncHTTPHandler:
     # Mirrors LiteLLMAiohttpTransport._background_close_tasks.
     _finalizer_close_tasks: ClassVar[set["asyncio.Task[None]"]] = set()  # mutable-ok: strong refs for pending closes
 
+    @classmethod
+    async def _close_client_at_finalization(cls, client: httpx.AsyncClient) -> None:
+        try:
+            await client.aclose()
+        except (OSError, RuntimeError) as exc:
+            verbose_logger.debug("Error closing client at finalization: %s", exc)
+        finally:
+            task: Final = asyncio.current_task()
+            if task is not None:
+                cls._finalizer_close_tasks.discard(task)
+
     @classmethod
     def _on_finalizer_close_done(cls, task: "asyncio.Task[None]") -> None:
         cls._finalizer_close_tasks.discard(task)
@@ -1272,8 +1283,8 @@ class AsyncHTTPHandler:
                 # here is the cross-loop path the transport refuses.
                 self._dispose_wrapped_aiohttp_session()
                 return
-            task: Final = loop.create_task(self._client.aclose())
             cls: Final = type(self)
+            task: Final = loop.create_task(cls._close_client_at_finalization(self._client))
             cls._finalizer_close_tasks.add(task)
             task.add_done_callback(cls._on_finalizer_close_done)
         except Exception:
@@ -1973,7 +1984,7 @@ def get_httpx_client(params: dict | None = None) -> HTTPHandler:
         cache = LLMClientCache()
         setattr(litellm, "in_memory_llm_clients_cache", cache)
 
-    _cached_client: Final = cache.get_cache(_cache_key_name)
+    _cached_client: Final = cache.get_cache(_cache_key_name, loop_bound=False)
     if _cached_client:
         return _cached_client
 
@@ -1989,6 +2000,7 @@ def get_httpx_client(params: dict | None = None) -> HTTPHandler:
         value=_new_client,
         ttl=_DEFAULT_TTL_FOR_HTTPX_CLIENTS,
         litellm_owned_client=True,
+        loop_bound=False,
     )
     return _new_client
 
diff --git a/litellm/llms/openai/common_utils.py b/litellm/llms/openai/common_utils.py
index a9d2dcdffb8..6c416124d1a 100644
--- a/litellm/llms/openai/common_utils.py
+++ b/litellm/llms/openai/common_utils.py
@@ -275,6 +275,10 @@ def build_output_token_limit_response(
     return e.response.headers, (_aiter_once(chunk) if is_async else _iter_once(chunk))
 
 
+def _is_loop_bound(client_initialization_params: Mapping[str, object]) -> bool:
+    return client_initialization_params.get("is_async") is not False
+
+
 class BaseOpenAILLM:
     """
     Base class for OpenAI LLMs for getting their httpx clients and SSL verification settings
@@ -289,7 +293,9 @@ class BaseOpenAILLM:
             client_initialization_params=client_initialization_params,
             client_type=client_type,
         )
-        _cached_client: Final = litellm.in_memory_llm_clients_cache.get_cache(_cache_key)
+        _cached_client: Final = litellm.in_memory_llm_clients_cache.get_cache(
+            _cache_key, loop_bound=_is_loop_bound(client_initialization_params)
+        )
         return _cached_client
 
     @staticmethod
@@ -330,6 +336,7 @@ class BaseOpenAILLM:
             value=openai_client,
             ttl=_DEFAULT_TTL_FOR_HTTPX_CLIENTS,
             litellm_owned_client=litellm_owned_client,
+            loop_bound=_is_loop_bound(client_initialization_params),
         )
 
     @staticmethod
diff --git a/tests/unit/caching/_event_loop_reuse.py b/tests/unit/caching/_event_loop_reuse.py
new file mode 100644
index 00000000000..97cf8fe31f0
--- /dev/null
+++ b/tests/unit/caching/_event_loop_reuse.py
@@ -0,0 +1,20 @@
+from collections.abc import Callable
+from typing import Final, TypeVar
+
+import pytest
+
+LoopResult = TypeVar("LoopResult")
+
+
+def runs_until_a_loop_address_repeats(
+    run_on_new_loop: Callable[[], tuple[int, LoopResult]],
+    earlier: tuple[tuple[int, LoopResult], ...] = (),
+    limit: int = 50,
+) -> tuple[tuple[int, LoopResult], ...]:
+    if len(earlier) == limit:
+        pytest.skip(f"none of {limit} collected loops had its address handed to a later loop")
+    latest: Final = run_on_new_loop()
+    runs: Final = (*earlier, latest)
+    if latest[0] in {loop_id for loop_id, _ in earlier}:
+        return runs
+    return runs_until_a_loop_address_repeats(run_on_new_loop, runs, limit)
diff --git a/tests/unit/caching/test_evicted_client_closer.py b/tests/unit/caching/test_evicted_client_closer.py
index 7679e276621..936eb37a733 100644
--- a/tests/unit/caching/test_evicted_client_closer.py
+++ b/tests/unit/caching/test_evicted_client_closer.py
@@ -10,6 +10,7 @@ never closed, because litellm does not own its lifecycle.
 import asyncio
 import gc
 import weakref
+from typing import Final
 from unittest.mock import AsyncMock
 
 import httpx
@@ -18,6 +19,7 @@ from redis.asyncio import ConnectionPool, Redis
 
 from litellm.caching.evicted_client_closer import EvictedClientCloser
 from litellm.llms.custom_httpx.http_handler import AsyncHTTPHandler
+from tests.unit.caching._event_loop_reuse import runs_until_a_loop_address_repeats
 
 
 class FakeClock:
@@ -41,6 +43,14 @@ class AsyncClient:
         self.closed = True
 
 
+class RecordingAsyncClient:
+    def __init__(self) -> None:
+        self.close_calls = 0
+
+    async def aclose(self) -> None:
+        self.close_calls += 1
+
+
 class SyncClient:
     def __init__(self) -> None:
         self.closed = False
@@ -266,6 +276,100 @@ def test_sync_client_evicted_outside_an_event_loop_is_still_closed():
     assert closer.pending_count == 0
 
 
+def test_async_client_from_collected_loop_is_not_closed_by_fresh_loops() -> None:
+    clock: Final = FakeClock()
+    closer: Final = EvictedClientCloser(grace_seconds=0, clock=clock)
+
+    async def reap_then_schedule(client: RecordingAsyncClient) -> None:
+        closer.reap()
+        await asyncio.sleep(0)
+        closer.schedule(client)
+
+    def run_on_new_loop() -> tuple[int, RecordingAsyncClient]:
+        client: Final = RecordingAsyncClient()
+        closer.mark_owned(client)
+        loop: Final = asyncio.new_event_loop()
+        loop_id: Final = id(loop)
+        try:
+            loop.run_until_complete(reap_then_schedule(client))
+        finally:
+            loop.close()
+        del loop
+        gc.collect()
+        return loop_id, client
+
+    runs: Final = runs_until_a_loop_address_repeats(run_on_new_loop)
+
+    assert all(client.close_calls == 0 for _, client in runs)
+
+
+def test_async_client_queued_on_a_live_loop_is_closed_only_by_that_loop() -> None:
+    clock: Final = FakeClock()
+    closer: Final = EvictedClientCloser(grace_seconds=0, clock=clock)
+    client: Final = RecordingAsyncClient()
+    closer.mark_owned(client)
+    owner_loop: Final = asyncio.new_event_loop()
+    other_loop: Final = asyncio.new_event_loop()
+
+    async def schedule() -> None:
+        closer.schedule(client)
+
+    async def reap() -> None:
+        closer.reap()
+        await asyncio.sleep(0)
+
+    try:
+        owner_loop.run_until_complete(schedule())
+        other_loop.run_until_complete(reap())
+        closes_after_other_loop_reaped: Final = client.close_calls
+        pending_after_other_loop_reaped: Final = closer.pending_count
+        owner_loop.run_until_complete(reap())
+    finally:
+        other_loop.close()
+        owner_loop.close()
+
+    assert closes_after_other_loop_reaped == 0
+    assert pending_after_other_loop_reaped == 1
+    assert client.close_calls == 1
+    assert closer.pending_count == 0
+
+
+def test_closes_queued_on_a_collected_loop_free_capacity() -> None:
+    clock: Final = FakeClock()
+    closer: Final = EvictedClientCloser(grace_seconds=0, max_pending=1, clock=clock)
+    first: Final = RecordingAsyncClient()
+    closer.mark_owned(first)
+    loop_a: Final = asyncio.new_event_loop()
+
+    async def schedule_first() -> None:
+        closer.schedule(first)
+
+    try:
+        loop_a.run_until_complete(schedule_first())
+    finally:
+        loop_a.close()
+    del loop_a
+    gc.collect()
+
+    second: Final = RecordingAsyncClient()
+    closer.mark_owned(second)
+    loop_b: Final = asyncio.new_event_loop()
+
+    async def schedule_and_reap_second() -> None:
+        closer.schedule(second)
+        closer.reap()
+        await asyncio.sleep(0)
+
+    try:
+        loop_b.run_until_complete(schedule_and_reap_second())
+    finally:
+        loop_b.close()
+
+    assert first.close_calls == 0
+    assert second.close_calls == 1
+    assert closer.pending_count == 0
+
+
 @pytest.mark.asyncio
 async def test_an_async_client_waits_for_a_loop_rather_than_being_dropped():
     clock = FakeClock()
@@ -289,8 +393,7 @@ async def test_an_async_client_waits_for_a_loop_rather_than_being_dropped():
 
 
 @pytest.mark.asyncio
-async def test_a_client_evicted_on_another_event_loop_is_left_alone():
-    """Closing a client bound to a different loop would schedule work on that loop."""
+async def test_a_client_evicted_on_a_collected_loop_is_dropped():
     clock = FakeClock()
     closer = make_closer(clock)
     client = AsyncClient()
@@ -310,7 +413,7 @@ async def test_a_client_evicted_on_another_event_loop_is_left_alone():
     await asyncio.sleep(0.05)
 
     assert client.closed is False
-    assert closer.pending_count == 1
+    assert closer.pending_count == 0
 
 
 @pytest.mark.asyncio
diff --git a/tests/unit/caching/test_llm_caching_handler.py b/tests/unit/caching/test_llm_caching_handler.py
index a3efd5d97aa..465ba2f9150 100644
--- a/tests/unit/caching/test_llm_caching_handler.py
+++ b/tests/unit/caching/test_llm_caching_handler.py
@@ -10,6 +10,7 @@ See: https://github.com/BerriAI/litellm/pull/22247
 
 import asyncio, gc, httpx, importlib, litellm, os, threading, time, weakref
 import warnings
+from typing import Final
 
 import aiohttp
 import pytest
@@ -29,6 +30,41 @@ from litellm.llms.custom_httpx.http_handler import(
 from litellm.types.utils import LlmProviders
 from litellm.utils import _invalidate_model_cost_lowercase_map
 from tests._vcr_conftest_common import install_live_call_probe, record_vcr_outcome
+from tests.unit.caching._event_loop_reuse import runs_until_a_loop_address_repeats
+
+
+async def _get_and_set_cache(cache: LLMClientCache) -> object | None:
+    cached: Final = await cache.async_get_cache("client")
+    await cache.async_set_cache("client", object())
+    return cached
+
+
+def _cache_result_on_new_loop(cache: LLMClientCache) -> tuple[int, object | None]:
+    loop: Final = asyncio.new_event_loop()
+    loop_id: Final = id(loop)
+    try:
+        result: Final = loop.run_until_complete(_get_and_set_cache(cache))
+    finally:
+        loop.close()
+    del loop
+    gc.collect()
+    return loop_id, result
+
+
+async def _get_cache_key(cache: LLMClientCache) -> str:
+    return cache.update_cache_key_with_event_loop("client")
+
+
+def _cache_key_on_new_loop(cache: LLMClientCache) -> tuple[int, str]:
+    loop: Final = asyncio.new_event_loop()
+    loop_id: Final = id(loop)
+    try:
+        key: Final = loop.run_until_complete(_get_cache_key(cache))
+    finally:
+        loop.close()
+    del loop
+    gc.collect()
+    return loop_id, key
 
 
 class MockAsyncClient:
@@ -51,6 +87,44 @@ class MockSyncClient:
         self.closed = True
 
 
+def test_async_client_cache_does_not_reuse_clients_between_collected_loops() -> None:
+    cache: Final = LLMClientCache()
+    runs: Final = runs_until_a_loop_address_repeats(lambda: _cache_result_on_new_loop(cache))
+
+    assert all(result is None for _, result in runs)
+
+
+def test_async_client_cache_keys_differ_for_every_collected_loop() -> None:
+    cache: Final = LLMClientCache()
+    runs: Final = runs_until_a_loop_address_repeats(lambda: _cache_key_on_new_loop(cache))
+    keys: Final = tuple(key for _, key in runs)
+
+    assert len(set(keys)) == len(keys)
+
+
+class _LoopWithoutWeakReferences:
+    __slots__ = ()
+
+
+def _cache_key_while_running(cache: LLMClientCache, loop: _LoopWithoutWeakReferences) -> str:
+    asyncio._set_running_loop(loop)
+    try:
+        return cache.update_cache_key_with_event_loop("client")
+    finally:
+        asyncio._set_running_loop(None)
+
+
+def test_cache_keys_stay_per_loop_on_loops_without_weak_references() -> None:
+    cache: Final = LLMClientCache()
+    loop_a: Final = _LoopWithoutWeakReferences()
+    loop_b: Final = _LoopWithoutWeakReferences()
+
+    first_key_on_a: Final = _cache_key_while_running(cache, loop_a)
+
+    assert _cache_key_while_running(cache, loop_a) == first_key_on_a
+    assert _cache_key_while_running(cache, loop_b) != first_key_on_a
+
+
 @pytest.mark.asyncio
 async def test_remove_key_does_not_close_async_client():
     """
diff --git a/tests/unit/integrations/test_agentops.py b/tests/unit/integrations/test_agentops.py
index 5d4055ac75f..629722f8602 100644
--- a/tests/unit/integrations/test_agentops.py
+++ b/tests/unit/integrations/test_agentops.py
@@ -1,10 +1,14 @@
 import os
+from typing import Final
 from unittest.mock import MagicMock, patch
 
 import pytest
+import respx
 
-
+import litellm
+from litellm.caching.llm_caching_handler import LLMClientCache
 from litellm.integrations.agentops.agentops import AgentOps, AgentOpsConfig
+from litellm.llms.custom_httpx.http_handler import get_httpx_client
 
 
 @pytest.fixture
@@ -111,3 +115,17 @@ def test_agentops_initialization_no_auth():
     assert agentops.resource_attributes["deployment.environment"] == "test_env"
     assert agentops.resource_attributes["telemetry.sdk.name"] == "agentops"
     assert "project.id" not in agentops.resource_attributes
+
+
+def test_auth_fetch_leaves_the_shared_sync_client_open_for_other_callers(
+    monkeypatch: pytest.MonkeyPatch, respx_mock: respx.MockRouter
+) -> None:
+    monkeypatch.setattr(litellm, "in_memory_llm_clients_cache", LLMClientCache())
+    auth_endpoint: Final = "https://agentops.example/v3/auth/token"
+    respx_mock.post(auth_endpoint).respond(json={"token": "jwt", "project_id": "project-1"})
+    client_another_caller_is_using: Final = get_httpx_client().client
+
+    agentops: Final = AgentOps(config=AgentOpsConfig(api_key="key", auth_endpoint=auth_endpoint))
+
+    assert agentops.resource_attributes["project.id"] == "project-1"
+    assert not client_another_caller_is_using.is_closed
diff --git a/tests/unit/llms/custom_httpx/test_http_handler.py b/tests/unit/llms/custom_httpx/test_http_handler.py
index cd3b377b943..0163cb9b26d 100644
--- a/tests/unit/llms/custom_httpx/test_http_handler.py
+++ b/tests/unit/llms/custom_httpx/test_http_handler.py
@@ -1388,6 +1388,55 @@ async def test_finalizer_with_running_loop_schedules_close_and_holds_task_ref():
     assert not (AsyncHTTPHandler._finalizer_close_tasks & scheduled)
 
 
+async def _drop_unused_handler() -> None:
+    AsyncHTTPHandler(timeout=61.0)
+    gc.collect()
+
+
+def test_finalizer_close_does_not_keep_a_loop_closed_right_after_it_alive():
+    loop: Final = asyncio.new_event_loop()
+    loop.run_until_complete(_drop_unused_handler())
+    loop.close()
+    closed_loop: Final = weakref.ref(loop)
+    del loop
+    gc.collect()
+
+    assert closed_loop() is None
+
+
+class _TransportFailingToClose(httpx.AsyncBaseTransport):
+    async def aclose(self) -> None:
+        raise RuntimeError("close failed")
+
+
+async def _drop_handler_whose_close_fails() -> None:
+    AsyncHTTPHandler(timeout=61.0, transport=_TransportFailingToClose())
+    gc.collect()
+
+
+def test_failed_finalizer_close_in_a_loops_last_step_reports_no_unretrieved_exception():
+    loop: Final = asyncio.new_event_loop()
+    exception_handler: Final = MagicMock()
+    loop.set_exception_handler(exception_handler)
+    loop.run_until_complete(_drop_handler_whose_close_fails())
+    loop.close()
+    del loop
+    gc.collect()
+
+    exception_handler.assert_not_called()
+
+
+async def _sync_client_with_timeout_62() -> HTTPHandler:
+    return get_httpx_client(params={"timeout": 62.0})
+
+
+def test_sync_client_is_shared_by_short_lived_loops_and_callers_outside_a_loop():
+    built_in_first_loop: Final = asyncio.run(_sync_client_with_timeout_62())
+
+    assert asyncio.run(_sync_client_with_timeout_62()) is built_in_first_loop
+    assert get_httpx_client(params={"timeout": 62.0}) is built_in_first_loop
+
+
 @pytest.mark.asyncio
 async def test_sync_close_helper_respects_session_ownership():
     """The loop-less fallback closes only sessions the transport owns; a
diff --git a/tests/unit/llms/openai/test_openai_common_utils.py b/tests/unit/llms/openai/test_openai_common_utils.py
index 206fd13260c..46c14fcfd8f 100644
--- a/tests/unit/llms/openai/test_openai_common_utils.py
+++ b/tests/unit/llms/openai/test_openai_common_utils.py
@@ -1,3 +1,4 @@
+import asyncio
 from typing import Final
 from unittest.mock import MagicMock, patch
 
@@ -154,6 +155,28 @@ def test_get_openai_client_initialization_param_fields(client_type):
     assert "self" not in result
 
 
+def _loop_test_client_params(is_async: bool) -> dict[str, object]:
+    return {"api_key": "sk-loop-scope-test", "is_async": is_async}
+
+
+async def _cache_openai_client(client: openai.OpenAI | openai.AsyncOpenAI, is_async: bool) -> None:
+    BaseOpenAILLM.set_cached_openai_client(client, "openai", _loop_test_client_params(is_async))
+
+
+async def _cached_openai_client(is_async: bool) -> object:
+    return BaseOpenAILLM.get_cached_openai_client(_loop_test_client_params(is_async), "openai")
+
+
+def test_sync_openai_client_cached_in_one_loop_is_reused_by_the_next_while_async_is_not():
+    sync_client: Final = openai.OpenAI(api_key="sk-loop-scope-test")
+    async_client: Final = openai.AsyncOpenAI(api_key="sk-loop-scope-test")
+    asyncio.run(_cache_openai_client(sync_client, is_async=False))
+    asyncio.run(_cache_openai_client(async_client, is_async=True))
+
+    assert asyncio.run(_cached_openai_client(is_async=False)) is sync_client
+    assert asyncio.run(_cached_openai_client(is_async=True)) is None
+
+
 @pytest.mark.parametrize("client_type", ["openai", "azure"])
 def test_get_openai_client_cache_key(client_type):
     """Verify get_openai_client_cache_key doesn't raise on tuple + tuple concatenation."""