diff --git a/Public/grid.js b/Public/grid.js
index bc4ceda..7a6c903 100644
--- a/Public/grid.js
+++ b/Public/grid.js
@@ -78,6 +78,10 @@ imageCanvas.addEventListener("click", function(event) {
 
     const currentPosition = row * numberOfColumns + column;
 
+    if (currentPosition >= numberOfCaps) {
+        return;
+    }
+
     if (selectedPosition === null) {
         selectedPosition = currentPosition;
         const circlePositionX = rowIsEven ? column * capImageSize + halfCapImageSize : column * capImageSize;