diff --git a/src/csharp/Grpc.Examples/MathGrpc.cs b/src/csharp/Grpc.Examples/MathGrpc.cs
index f008a0d7f2f8976bf3e2882dc1c792f0584d65c1..1395a80010714d7ca1f364ee1e884665b74b104b 100644
--- a/src/csharp/Grpc.Examples/MathGrpc.cs
+++ b/src/csharp/Grpc.Examples/MathGrpc.cs
@@ -5,7 +5,6 @@
 using System;
 using System.Threading;
 using System.Threading.Tasks;
-using Google.Protobuf;
 using Grpc.Core;
 
 namespace Math {
@@ -13,7 +12,7 @@ namespace Math {
   {
     static readonly string __ServiceName = "math.Math";
 
-    static readonly Marshaller<global::Math.DivArgs> __Marshaller_DivArgs = Marshallers.Create((arg) => arg.ToByteArray(), global::Math.DivArgs.Parser.ParseFrom);
+    static readonly Marshaller<global::Math.DivArgs> __Marshaller_DivArgs = Marshallers.Create((arg) => global::Google.Protobuf.MessageExtensions.ToByteArray(arg), global::Math.DivArgs.Parser.ParseFrom);
     static readonly Marshaller<global::Math.DivReply> __Marshaller_DivReply = Marshallers.Create((arg) => arg.ToByteArray(), global::Math.DivReply.Parser.ParseFrom);
     static readonly Marshaller<global::Math.FibArgs> __Marshaller_FibArgs = Marshallers.Create((arg) => arg.ToByteArray(), global::Math.FibArgs.Parser.ParseFrom);
     static readonly Marshaller<global::Math.Num> __Marshaller_Num = Marshallers.Create((arg) => arg.ToByteArray(), global::Math.Num.Parser.ParseFrom);