diff --git a/client/widgets/CExchangeController.cpp b/client/widgets/CExchangeController.cpp
index 0b2c25683..eb640a46c 100644
--- a/client/widgets/CExchangeController.cpp
+++ b/client/widgets/CExchangeController.cpp
@@ -79,6 +79,10 @@ void CExchangeController::moveArmy(bool leftToRight, std::optional<SlotID> heldS
 			});
 		heldSlot = weakestSlot->first;
 	}
+	
+	if (source->getCreature(heldSlot.value()) == nullptr)
+		return;
+
 	LOCPLINT->cb->bulkMoveArmy(source->id, target->id, heldSlot.value());
 }