diff --git a/src/main/java/com/replaymod/core/versions/MCVer.java b/src/main/java/com/replaymod/core/versions/MCVer.java
index 80c165f5..d62db95d 100644
--- a/src/main/java/com/replaymod/core/versions/MCVer.java
+++ b/src/main/java/com/replaymod/core/versions/MCVer.java
@@ -394,6 +394,14 @@ public class MCVer {
         //#endif
     }
 
+    public static void scheduleOnMainThread(Runnable runnable) {
+        //#if MC>=11400
+        getMinecraft().send(runnable);
+        //#else
+        //$$ getMinecraft().addScheduledTask(runnable);
+        //#endif
+    }
+
     //#if MC>=11400
     public static Window getWindow(MinecraftClient mc) {
         //#if MC>=11500
diff --git a/src/main/java/com/replaymod/recording/mixin/MixinNetHandlerPlayClient.java b/src/main/java/com/replaymod/recording/mixin/MixinNetHandlerPlayClient.java
index 997bdb11..497a18ec 100644
--- a/src/main/java/com/replaymod/recording/mixin/MixinNetHandlerPlayClient.java
+++ b/src/main/java/com/replaymod/recording/mixin/MixinNetHandlerPlayClient.java
@@ -57,6 +57,7 @@ public abstract class MixinNetHandlerPlayClient {
     //$$ @Inject(method = "handlePlayerListItem", at=@At("HEAD"))
     //#endif
     public void recordOwnJoin(PlayerListS2CPacket packet, CallbackInfo ci) {
+        if (!MCVer.isOnMainThread()) return;
         if (mcStatic.player == null) return;
 
         RecordingEventHandler handler = getRecordingEventHandler();
diff --git a/src/main/java/com/replaymod/recording/packet/PacketListener.java b/src/main/java/com/replaymod/recording/packet/PacketListener.java
index 2fb03ed8..9bcd7d17 100644
--- a/src/main/java/com/replaymod/recording/packet/PacketListener.java
+++ b/src/main/java/com/replaymod/recording/packet/PacketListener.java
@@ -149,6 +149,14 @@ public class PacketListener extends ChannelInboundHandlerAdapter {
     }
 
     public void save(Packet packet) {
+        // If we're not on the main thread (i.e. we're on the netty thread), then we need to schedule the saving
+        // to happen on the main thread so we can guarantee correct ordering of inbound and inject packets.
+        // Otherwise, injected packets may end up further down the packet stream than they were supposed to and other
+        // inbound packets which may rely on the injected packet would behave incorrectly when played back.
+        if (!MCVer.isOnMainThread()) {
+            MCVer.scheduleOnMainThread(() -> save(packet));
+            return;
+        }
         try {
             if(packet instanceof PlayerSpawnS2CPacket) {
                 //#if MC>=10800