diff --git a/sdk/src/server-api/sc/protocol/requests/ControlTimeoutRequest.kt b/sdk/src/server-api/sc/protocol/requests/ControlTimeoutRequest.kt
index af4e5defc..e4c172db9 100644
--- a/sdk/src/server-api/sc/protocol/requests/ControlTimeoutRequest.kt
+++ b/sdk/src/server-api/sc/protocol/requests/ControlTimeoutRequest.kt
@@ -4,6 +4,8 @@ import com.thoughtworks.xstream.annotations.XStreamAlias
 import com.thoughtworks.xstream.annotations.XStreamAsAttribute
 
 /** Used to change whether a player in a slot can time out. */
+// TODO this shouldn't need changing after a game was started
+// instead, a game should be preparable without reservations
 @XStreamAlias("timeout")
 data class ControlTimeoutRequest(
         @XStreamAsAttribute
diff --git a/server/src/sc/server/Lobby.kt b/server/src/sc/server/Lobby.kt
index a722f0b8a..b99e48f0b 100644
--- a/server/src/sc/server/Lobby.kt
+++ b/server/src/sc/server/Lobby.kt
@@ -84,8 +84,10 @@ open class Lobby: GameRoomManager(), IClientListener, Closeable {
                     }
                     is ControlTimeoutRequest -> {
                         val room = this.findRoom(packet.roomId)
+                        room.ensureOpenSlots(packet.slot + 1)
                         val slot = room.slots[packet.slot]
-                        slot.role.player.canTimeout = packet.activate
+                        slot.descriptor = slot.descriptor.copy(canTimeout = packet.activate)
+                        slot.role?.player?.canTimeout = packet.activate
                     }
                     is ObservationRequest -> {
                         val room = this.findRoom(packet.roomId)
diff --git a/server/src/sc/server/gaming/GameRoom.java b/server/src/sc/server/gaming/GameRoom.java
index 6888f2149..f743dc3e4 100644
--- a/server/src/sc/server/gaming/GameRoom.java
+++ b/server/src/sc/server/gaming/GameRoom.java
@@ -384,6 +384,23 @@ public List<PlayerSlot> getSlots() {
     return Collections.unmodifiableList(this.playerSlots);
   }
 
+  public void ensureOpenSlots(int count) throws TooManyPlayersException {
+    if (count > getMaximumPlayerCount()) {
+      throw new TooManyPlayersException();
+    }
+    while (playerSlots.size() < count) {
+      this.playerSlots.add(new PlayerSlot(this));
+    }
+  }
+
+  /** Set descriptors of PlayerSlots. */
+  public void openSlots(SlotDescriptor[] descriptors) throws TooManyPlayersException {
+    ensureOpenSlots(descriptors.length);
+    for (int i = 0; i < descriptors.length; i++) {
+      this.playerSlots.get(i).setDescriptor(descriptors[i]);
+    }
+  }
+
   /**
    * Threadsafe method to reserve all PlayerSlots.
    *
@@ -538,20 +555,6 @@ public void onPaused(Player nextPlayer) {
     observerBroadcast(new RoomPacket(getId(), new GamePausedEvent(nextPlayer)));
   }
 
-  /** Set descriptors of PlayerSlots. */
-  public void openSlots(SlotDescriptor[] descriptors)
-          throws TooManyPlayersException {
-    if (descriptors.length > getMaximumPlayerCount()) {
-      throw new TooManyPlayersException();
-    }
-    this.playerSlots.add(new PlayerSlot(this));
-    this.playerSlots.add(new PlayerSlot(this));
-
-    for (int i = 0; i < descriptors.length; i++) {
-      this.playerSlots.get(i).setDescriptor(descriptors[i]);
-    }
-  }
-
   /** Return true if GameStatus is OVER. */
   public boolean isOver() {
     return getStatus() == GameStatus.OVER;