diff --git a/vllm/v1/worker/gpu_model_runner.py b/vllm/v1/worker/gpu_model_runner.py
index 7c88ecc31d02..1d093ba0582a 100644
--- a/vllm/v1/worker/gpu_model_runner.py
+++ b/vllm/v1/worker/gpu_model_runner.py
@@ -454,7 +454,7 @@ def _update_states(self, scheduler_output: "SchedulerOutput") -> None:
 
         # Add the new or resumed requests to the persistent batch.
         # The smaller empty indices are filled first.
-        removed_req_indices = sorted(removed_req_indices, reverse=True)
+        removed_req_indices.sort(reverse=True)
         for req_id in req_ids_to_add:
             req_state = self.requests[req_id]
             if removed_req_indices: