diff --git a/src/test/test_funktionen.c b/src/test/test_funktionen.c
index 62dafa7..cbcb1b4 100644
--- a/src/test/test_funktionen.c
+++ b/src/test/test_funktionen.c
@@ -228,6 +228,21 @@ void test_o_wins_onIndex_00_10_20(void)
     TEST_ASSERT_EQUAL_INT(expected, actual);
 }
 
+void test_o_wins_onIndex_01_11_21(void)
+{
+    /* arrange */
+    int actual;
+    int expected = 1;
+    
+    char board[][3] = {{' ','O',' '}, {' ','O',' '}, {' ','O',' '}};
+
+    /* act */
+    actual = o_wins_01_11_21(board);
+
+    /* assert */
+    TEST_ASSERT_EQUAL_INT(expected, actual);
+}
+
 void test_stringLaenge_von_Kokosnuss(void)
 {
     /* arrange */