diff --git a/backend/requests/test.http b/backend/requests/blackjack.http
similarity index 100%
rename from backend/requests/test.http
rename to backend/requests/blackjack.http
diff --git a/backend/src/main/java/de/szut/casino/blackjack/BlackJackGameController.java b/backend/src/main/java/de/szut/casino/blackjack/BlackJackGameController.java
index e0c6378..cb8f6fd 100644
--- a/backend/src/main/java/de/szut/casino/blackjack/BlackJackGameController.java
+++ b/backend/src/main/java/de/szut/casino/blackjack/BlackJackGameController.java
@@ -57,6 +57,7 @@ public class BlackJackGameController {
         }
 
         BlackJackGameEntity game = new BlackJackGameEntity();
+        game.setUser(user);
         game.setBet(betAmount);
 
         user.setBalance(user.getBalance().subtract(betAmount));
@@ -64,5 +65,6 @@ public class BlackJackGameController {
         userRepository.save(user);
         blackJackGameRepository.save(game);
 
-        return ResponseEntity.ok(game);    }
+        return ResponseEntity.ok(game);
+    }
 }
diff --git a/backend/src/main/java/de/szut/casino/blackjack/BlackJackGameEntity.java b/backend/src/main/java/de/szut/casino/blackjack/BlackJackGameEntity.java
index b9687c4..9625c92 100644
--- a/backend/src/main/java/de/szut/casino/blackjack/BlackJackGameEntity.java
+++ b/backend/src/main/java/de/szut/casino/blackjack/BlackJackGameEntity.java
@@ -1,8 +1,7 @@
 package de.szut.casino.blackjack;
 
-import jakarta.persistence.Entity;
-import jakarta.persistence.GeneratedValue;
-import jakarta.persistence.Id;
+import de.szut.casino.user.UserEntity;
+import jakarta.persistence.*;
 import lombok.AllArgsConstructor;
 import lombok.Getter;
 import lombok.NoArgsConstructor;
@@ -20,6 +19,9 @@ public class BlackJackGameEntity {
     @Id
     @GeneratedValue
     private Long id;
+    @ManyToOne
+    @JoinColumn(name = "user_id", nullable = false)
+    private UserEntity user;
     private String state;
     private BigDecimal bet;
 }
diff --git a/backend/src/main/java/de/szut/casino/blackjack/Card.java b/backend/src/main/java/de/szut/casino/blackjack/CardEntity.java
similarity index 68%
rename from backend/src/main/java/de/szut/casino/blackjack/Card.java
rename to backend/src/main/java/de/szut/casino/blackjack/CardEntity.java
index 2547739..f03a5a1 100644
--- a/backend/src/main/java/de/szut/casino/blackjack/Card.java
+++ b/backend/src/main/java/de/szut/casino/blackjack/CardEntity.java
@@ -4,11 +4,11 @@ package de.szut.casino.blackjack;
 import lombok.Getter;
 
 @Getter
-public class Card {
+public class CardEntity {
     private final Suit suit;
     private final Rank rank;
 
-    public Card(Suit suit, Rank rank) {
+    public CardEntity(Suit suit, Rank rank) {
         this.suit = suit;
         this.rank = rank;
     }