diff --git a/BlazorSolution/MiniGames/Shared/Models/TicTacToeBrett.cs b/BlazorSolution/MiniGames/Shared/Models/TicTacToeBrett.cs
index 59468c8..4fe20d0 100644
--- a/BlazorSolution/MiniGames/Shared/Models/TicTacToeBrett.cs
+++ b/BlazorSolution/MiniGames/Shared/Models/TicTacToeBrett.cs
@@ -100,6 +100,11 @@ namespace MiniGames.Shared.Models
                 }
             }
 
+            if (dreiGleichGefuellt(Felder[0, 0], Felder[1, 1], Felder[2, 2]))
+            {
+                return Felder[0, 0];
+            }
+
             return LEER;
         }
     }
diff --git a/BlazorSolution/MiniGamesTests/TicTacToeBrettTest.cs b/BlazorSolution/MiniGamesTests/TicTacToeBrettTest.cs
index dcfa40c..9351135 100644
--- a/BlazorSolution/MiniGamesTests/TicTacToeBrettTest.cs
+++ b/BlazorSolution/MiniGamesTests/TicTacToeBrettTest.cs
@@ -300,5 +300,23 @@ namespace MiniGamesTests
             // assert
             Assert.Equal(erwarteterGewinner, erhaltenerGewinner);
         }
+
+        [Fact]
+        public void Gewinner_DiagonaleReiheNWzuSO()
+        {
+            // arrange
+            TicTacToeBrett brett = TestBrett(
+                5, TicTacToeBrett.LEER, TicTacToeBrett.LEER,
+                TicTacToeBrett.LEER, 5, TicTacToeBrett.LEER,
+                TicTacToeBrett.LEER, TicTacToeBrett.LEER, 5
+            );
+            int erwarteterGewinner = 5;
+
+            // act
+            int erhaltenerGewinner = brett.Gewinner();
+
+            // assert
+            Assert.Equal(erwarteterGewinner, erhaltenerGewinner);
+        }
     }
 }