diff --git a/quic/core/tls_handshaker.h b/quic/core/tls_handshaker.h
index dba8ea5..3bfdac6 100644
--- a/quic/core/tls_handshaker.h
+++ b/quic/core/tls_handshaker.h
@@ -57,7 +57,7 @@
  protected:
   // Called when a new message is received on the crypto stream and is available
   // for the TLS stack to read.
-  void AdvanceHandshake();
+  virtual void AdvanceHandshake();
 
   void CloseConnection(QuicErrorCode error, const std::string& reason_phrase);
   // Closes the connection, specifying the wire error code |ietf_error|