diff --git a/src/test/c/test_VierGewinnt.c b/src/test/c/test_VierGewinnt.c
index 6896efe..6569d15 100644
--- a/src/test/c/test_VierGewinnt.c
+++ b/src/test/c/test_VierGewinnt.c
@@ -107,5 +107,16 @@ void test_checkWin_Vertical_X(void) {
 
 
 
+void test_checkWin_Vertical_O(void) {
+    char board[6][7] = {
+        {'X', 'O', ' ', ' ', ' ', ' ', ' '},
+        {'X', 'O', ' ', ' ', ' ', ' ', ' '},
+        {'X', 'O', ' ', ' ', ' ', ' ', ' '},
+        {' ', 'O', ' ', ' ', ' ', ' ', ' '},
+        {' ', ' ', ' ', ' ', ' ', ' ', ' '},
+        {' ', ' ', ' ', ' ', ' ', ' ', ' '}
+    };
 
+    TEST_ASSERT_EQUAL_INT(1, checkWin(board, 'O'));  // Vertikale Gewinnsituation für 'X'
+}