diff --git a/botorch/optim/core.py b/botorch/optim/core.py
index 691d55cf4b..b91e7be6cd 100644
--- a/botorch/optim/core.py
+++ b/botorch/optim/core.py
@@ -202,7 +202,7 @@ def torch_minimize(
         )
 
         # TODO: Update stopping_criterion API to return a message.
-        if stopping_criterion and stopping_criterion(fval):
+        if stopping_criterion and stopping_criterion(fval.detach()):
             result.status = OptimizationStatus.STOPPED
             result.message = "`torch_minimize` stopped due to `stopping_criterion`."