diff --git a/Mage/src/mage/game/combat/Combat.java b/Mage/src/mage/game/combat/Combat.java
index d4e287f0dd4..6171031f3b0 100644
--- a/Mage/src/mage/game/combat/Combat.java
+++ b/Mage/src/mage/game/combat/Combat.java
@@ -404,7 +404,7 @@ public class Combat implements Serializable, Copyable<Combat> {
             return;
         }
         Permanent defender = game.getPermanent(defenderId);
-        CombatGroup newGroup = new CombatGroup(defenderId, defender != null);
+        CombatGroup newGroup = new CombatGroup(defenderId, defender != null, defender != null ? defender.getControllerId(): defenderId);
         newGroup.attackers.add(attackerId);
         Permanent attacker = game.getPermanent(attackerId);
         if (!attacker.getAbilities().containsKey(VigilanceAbility.getInstance().getId())) {
@@ -419,7 +419,7 @@ public class Combat implements Serializable, Copyable<Combat> {
         Permanent blocker = game.getPermanent(blockerId);
         if (blockerId != null && blocker != null && blocker.getBlocking() > 1) {
             if (!blockingGroups.containsKey(blockerId)) {
-                CombatGroup newGroup = new CombatGroup(playerId, playerId != null);
+                CombatGroup newGroup = new CombatGroup(playerId, false, playerId);
                 newGroup.blockers.add(blockerId);
                 // add all blocked attackers
                 for (CombatGroup group : groups) {
diff --git a/Mage/src/mage/game/combat/CombatGroup.java b/Mage/src/mage/game/combat/CombatGroup.java
index 658fa14baee..758f2c10c83 100644
--- a/Mage/src/mage/game/combat/CombatGroup.java
+++ b/Mage/src/mage/game/combat/CombatGroup.java
@@ -52,12 +52,14 @@ public class CombatGroup implements Serializable, Copyable<CombatGroup> {
     protected List<UUID> attackerOrder = new ArrayList<UUID>();
     protected Map<UUID, UUID> players = new HashMap<UUID, UUID>();
     protected boolean blocked;
-    protected UUID defenderId;
+    protected UUID defenderId; // planeswalker or player
+    protected UUID defendingPlayerId;
     protected boolean defenderIsPlaneswalker;
 
-    public CombatGroup(UUID defenderId, boolean defenderIsPlaneswalker) {
+    public CombatGroup(UUID defenderId, boolean defenderIsPlaneswalker, UUID defendingPlayerId) {
         this.defenderId = defenderId;
         this.defenderIsPlaneswalker = defenderIsPlaneswalker;
+        this.defendingPlayerId = defendingPlayerId;
     }
 
     public CombatGroup(final CombatGroup group) {
@@ -379,6 +381,10 @@ public class CombatGroup implements Serializable, Copyable<CombatGroup> {
     }
 
     public boolean canBlock(Permanent blocker, Game game) {
+        // you can't block if combat group attacks another player
+        if (!defendingPlayerId.equals(blocker.getControllerId()) ) {
+            return false;
+        }
         for (UUID attackerId: attackers) {
             if (!blocker.canBlock(attackerId, game)) {
                 return false;