diff --git a/src/transformers/generation/utils.py b/src/transformers/generation/utils.py
index 77e67e7b2b0b17..43988780a3739a 100644
--- a/src/transformers/generation/utils.py
+++ b/src/transformers/generation/utils.py
@@ -692,13 +692,11 @@ def _update_model_kwargs_for_generation(
         if model_kwargs.get("use_cache", True):
             model_kwargs["cache_position"] = model_kwargs["cache_position"][-1:] + num_new_tokens
         else:
+            previous_positions = model_kwargs.pop("cache_position")
             new_positions = torch.arange(
-                model_kwargs["cache_position"][-1] + 1,
-                model_kwargs["cache_position"][-1] + num_new_tokens + 1,
-                device=model_kwargs["cache_position"].device,
-                dtype=model_kwargs["cache_position"].dtype,
+                previous_positions[-1] + 1, previous_positions[-1] + num_new_tokens + 1, device=previous_positions.device, dtype=previous_positions.dtype,
             )
-            model_kwargs["cache_position"] = torch.cat((model_kwargs["cache_position"], new_positions))
+            model_kwargs["cache_position"] = torch.cat((previous_positions, new_positions))
         return model_kwargs
 
     def _reorder_cache(self, past_key_values, beam_idx):