diff --git a/Grid/communicator/Communicator_mpi3.cc b/Grid/communicator/Communicator_mpi3.cc
index 31566352..cb03ca46 100644
--- a/Grid/communicator/Communicator_mpi3.cc
+++ b/Grid/communicator/Communicator_mpi3.cc
@@ -44,12 +44,15 @@ void CartesianCommunicator::Init(int *argc, char ***argv)
   MPI_Initialized(&flag); // needed to coexist with other libs apparently
   if ( !flag ) {
 
-// temporarily enable Fugaku/Tofu support by default
+// Fugaku Tofu: enable by default
 #if defined (A64FX) || defined (A64FXFIXEDSIZE)
+#ifndef TOFU
 #define TOFU
+#pragma message ("MPI_THREAD_SINGLE")
+#endif
 #endif
 
-#if defined (TOFU) // hack for FUGAKU, credits go to Issaku Kanamori
+#if defined (TOFU) // FUGAKU, credits go to Issaku Kanamori
     nCommThreads=1;
     MPI_Init(argc,argv);
 #else