diff --git a/tetris.cpp b/tetris.cpp
index e099a5d..1b74859 100644
--- a/tetris.cpp
+++ b/tetris.cpp
@@ -746,7 +746,8 @@ void updateShadow(SDLPP::Scene &scene) {
             auto colY = col->getPos().second;
             if(std::find(invalid_objects.begin(), invalid_objects.end(), col) != invalid_objects.end())
                 continue;
-            if(colY - curY < shadow_drop)
+            auto possible_drop = colY - curY;
+            if(possible_drop < shadow_drop && possible_drop >= 0)
                 shadow_drop = colY - curY;
         }
     }