diff --git a/litellm/llms/anthropic/experimental_pass_through/adapters/streaming_iterator.py b/litellm/llms/anthropic/experimental_pass_through/adapters/streaming_iterator.py
index 6bddad09f21..2675709090c 100644
--- a/litellm/llms/anthropic/experimental_pass_through/adapters/streaming_iterator.py
+++ b/litellm/llms/anthropic/experimental_pass_through/adapters/streaming_iterator.py
@@ -129,8 +129,6 @@ class AnthropicStreamWrapper(AdapterCompletionStreamWrapper):
 
                 if should_start_new_block and not self.sent_content_block_finish:
                     # Queue the sequence: content_block_stop -> content_block_start
-                    # The trigger chunk itself is not emitted as a delta since the
-                    # content_block_start already carries the relevant information.
                     self.chunk_queue.append(
                         {
                             "type": "content_block_stop",
@@ -144,6 +142,11 @@ class AnthropicStreamWrapper(AdapterCompletionStreamWrapper):
                             "content_block": self.current_content_block_start,
                         }
                     )
+                    # Also emit the trigger chunk as a delta when it carries
+                    # data (e.g. Gemini returns complete function-call arguments
+                    # in the same chunk that contains the function name).
+                    if processed_chunk.get("type") == "content_block_delta":
+                        self.chunk_queue.append(processed_chunk)
                     self.sent_content_block_finish = False
                     return self.chunk_queue.popleft()
 
@@ -305,8 +308,6 @@ class AnthropicStreamWrapper(AdapterCompletionStreamWrapper):
                 if not self.queued_usage_chunk:
                     if should_start_new_block and not self.sent_content_block_finish:
                         # Queue the sequence: content_block_stop -> content_block_start
-                        # The trigger chunk itself is not emitted as a delta since the
-                        # content_block_start already carries the relevant information.
 
                         # 1. Stop current content block
                         self.chunk_queue.append(
@@ -325,6 +326,12 @@ class AnthropicStreamWrapper(AdapterCompletionStreamWrapper):
                             }
                         )
 
+                        # 3. Also emit the trigger chunk as a delta when it
+                        # carries data (e.g. Gemini returns complete function-call
+                        # arguments in the same chunk that contains the function name).
+                        if processed_chunk.get("type") == "content_block_delta":
+                            self.chunk_queue.append(processed_chunk)
+
                         # Reset state for new block
                         self.sent_content_block_finish = False