diff --git a/src/main/java/forge/GuiDisplay.java b/src/main/java/forge/GuiDisplay.java
index 674e18fbabd..4eb1984bbde 100644
--- a/src/main/java/forge/GuiDisplay.java
+++ b/src/main/java/forge/GuiDisplay.java
@@ -692,6 +692,22 @@ public class GuiDisplay extends JFrame implements CardContainer, Display {
      * </p>
      */
     private void addObservers() {
+        // Remove all observers, placed by new UI.
+        AllZone.getHumanPlayer().deleteObservers();
+        AllZone.getHumanPlayer().getZone(Zone.Hand).deleteObservers();
+        AllZone.getHumanPlayer().getZone(Zone.Graveyard).deleteObservers();
+        AllZone.getHumanPlayer().getZone(Zone.Library).deleteObservers();
+        AllZone.getHumanPlayer().getZone(Zone.Battlefield).deleteObservers();
+
+        AllZone.getComputerPlayer().deleteObservers();
+        AllZone.getComputerPlayer().getZone(Zone.Hand).deleteObservers();
+        AllZone.getComputerPlayer().getZone(Zone.Graveyard).deleteObservers();
+        AllZone.getComputerPlayer().getZone(Zone.Library).deleteObservers();
+        AllZone.getComputerPlayer().getZone(Zone.Battlefield).deleteObservers();
+
+        AllZone.getStack().deleteObservers();
+        AllZone.getInputControl().deleteObservers();
+
         // long method
         final Observer o = new Observer() {
             @Override
diff --git a/src/main/java/forge/control/ControlMatchUI.java b/src/main/java/forge/control/ControlMatchUI.java
index 3e40a28a8cd..102d1828f6b 100644
--- a/src/main/java/forge/control/ControlMatchUI.java
+++ b/src/main/java/forge/control/ControlMatchUI.java
@@ -74,6 +74,22 @@ public class ControlMatchUI {
      * 
      */
     public void initMatch() {
+        // Remove all observers, placed by old UI.
+        AllZone.getHumanPlayer().deleteObservers();
+        AllZone.getHumanPlayer().getZone(Zone.Hand).deleteObservers();
+        AllZone.getHumanPlayer().getZone(Zone.Graveyard).deleteObservers();
+        AllZone.getHumanPlayer().getZone(Zone.Library).deleteObservers();
+        AllZone.getHumanPlayer().getZone(Zone.Battlefield).deleteObservers();
+
+        AllZone.getComputerPlayer().deleteObservers();
+        AllZone.getComputerPlayer().getZone(Zone.Hand).deleteObservers();
+        AllZone.getComputerPlayer().getZone(Zone.Graveyard).deleteObservers();
+        AllZone.getComputerPlayer().getZone(Zone.Library).deleteObservers();
+        AllZone.getComputerPlayer().getZone(Zone.Battlefield).deleteObservers();
+
+        AllZone.getStack().deleteObservers();
+        AllZone.getInputControl().deleteObservers();
+
         // All child components have been assembled; observers and listeners can
         // be added safely.
         this.view.getAreaSidebar().getTabber().getController().addObservers();