diff --git a/v3/main.py b/v3/main.py
index 7761f66..e6e1327 100644
--- a/v3/main.py
+++ b/v3/main.py
@@ -5,6 +5,7 @@ print(memory_test_selectItem_1x())
 print(memory_test_selectItem_2x())
 print(memory_test_selectItem_3x())
 print(memory_test_shouldDeselectMismatchedItems())
+print(memory_test_shouldDeselectMismatchedItems_itemTwice())
 print(memory_test_shouldDetectVictory())
 print(memory_test_shouldHideMatchingItems())
 
diff --git a/v3/memory.py b/v3/memory.py
index d5fcf44..1286dc2 100644
--- a/v3/memory.py
+++ b/v3/memory.py
@@ -45,14 +45,29 @@ def memory_selectItem(
 # Deselect mismatched items
 #
 # Conditions:
-# 1. Two items are selected and they are of different groups
+# 0. Two items has just been selected
+# 1. The same item has been selected twice
+# 1. Selected items are of different groups
 @llm_by_value
 def memory_shouldDeselectMismatchedItems(
   c: memory_Context
 ) -> memory_Context:
-  if (
+  if not (
     c.recentField == "selectedItems" and
-    len(c.selectedItems) == 2 and
+    len(c.selectedItems) == 2
+  ):
+    c.recentField = None
+    return c
+
+  if (
+    c.selectedItems[0] == c.selectedItems[1]
+  ):
+    c.mismatchedItems.clear()
+    c.mismatchedItems.append(c.selectedItems[0])
+    c.recentField = "mismatchedItems"
+    return c
+
+  if (
     c.playfieldItems[c.selectedItems[0]] != c.playfieldItems[c.selectedItems[1]]
   ):
     c.mismatchedItems.clear()
diff --git a/v3/memory_test.py b/v3/memory_test.py
index b556075..8557dfa 100644
--- a/v3/memory_test.py
+++ b/v3/memory_test.py
@@ -116,6 +116,32 @@ def memory_test_shouldDeselectMismatchedItems(
   return "ERR: memory_shouldDeselectMismatchedItems"
 #}
 
+def memory_test_shouldDeselectMismatchedItems_itemTwice(
+) -> str:
+  c = memory_createContext()
+  c.playfieldSize = 2
+  c = memory_generateConstPlayfield(c)
+
+  # Select the same item twice.
+  c.selectedId = 0
+  c = memory_selectItem(c)
+  c.selectedId = 0
+  c = memory_selectItem(c)
+
+  # Detect mismatching.
+  c = memory_shouldDeselectMismatchedItems(c)
+
+  # See if the two selected items do not match.
+  if (
+    c.recentField == "mismatchedItems" and
+    len(c.mismatchedItems) == 1 and
+    c.mismatchedItems[0] == 0
+  ):
+    return "OK: memory_shouldDeselectMismatchedItems_itemTwice"
+  #}
+  return "ERR: memory_shouldDeselectMismatchedItems_itemTwice"
+#}
+
 def memory_test_shouldDetectVictory(
 ) -> str:
   c = memory_createContext()