diff --git a/Assets/Mirror/Runtime/NetworkClient.cs b/Assets/Mirror/Runtime/NetworkClient.cs
index 6afef3e67..01c1c83ce 100644
--- a/Assets/Mirror/Runtime/NetworkClient.cs
+++ b/Assets/Mirror/Runtime/NetworkClient.cs
@@ -334,7 +334,7 @@ public static void RegisterHandler<T>(Action<T> handler, bool requireAuthenticat
         }
 
         /// <summary>Replace a handler for a particular message type. Should require authentication by default.</summary>
-        // TODO does anyone even use that? consider removing
+        [Obsolete("We are considering to remove ReplaceHandler<T>. If you have a good reason why we should keep it, please let us know.")]
         public static void ReplaceHandler<T>(Action<NetworkConnection, T> handler, bool requireAuthentication = true)
             where T : struct, NetworkMessage
         {
@@ -343,7 +343,7 @@ public static void ReplaceHandler<T>(Action<NetworkConnection, T> handler, bool
         }
 
         /// <summary>Replace a handler for a particular message type. Should require authentication by default.</summary>
-        // TODO does anyone even use that? consider removing
+        [Obsolete("We are considering to remove ReplaceHandler<T>. If you have a good reason why we should keep it, please let us know.")]
         public static void ReplaceHandler<T>(Action<T> handler, bool requireAuthentication = true)
             where T : struct, NetworkMessage
         {
diff --git a/Assets/Mirror/Runtime/NetworkServer.cs b/Assets/Mirror/Runtime/NetworkServer.cs
index af6695ab7..7dbbdbbf6 100644
--- a/Assets/Mirror/Runtime/NetworkServer.cs
+++ b/Assets/Mirror/Runtime/NetworkServer.cs
@@ -469,6 +469,7 @@ public static void RegisterHandler<T>(Action<T> handler, bool requireAuthenticat
         }
 
         /// <summary>Replace a handler for message type T. Most should require authentication.</summary>
+        [Obsolete("We are considering to remove ReplaceHandler<T>. If you have a good reason why we should keep it, please let us know.")]
         public static void ReplaceHandler<T>(Action<NetworkConnection, T> handler, bool requireAuthentication = true)
             where T : struct, NetworkMessage
         {
@@ -477,6 +478,7 @@ public static void ReplaceHandler<T>(Action<NetworkConnection, T> handler, bool
         }
 
         /// <summary>Replace a handler for message type T. Most should require authentication.</summary>
+        [Obsolete("We are considering to remove ReplaceHandler<T>. If you have a good reason why we should keep it, please let us know.")]
         public static void ReplaceHandler<T>(Action<T> handler, bool requireAuthentication = true)
             where T : struct, NetworkMessage
         {