diff --git a/devito/operator/operator.py b/devito/operator/operator.py
index 4f60d250f68..1c595d74015 100644
--- a/devito/operator/operator.py
+++ b/devito/operator/operator.py
@@ -959,8 +959,8 @@ def _emit_apply_profiling(self, args):
                         break
 
         if configuration['mpi']:
-            perf("Performance[mode=%s, mpi=%s] arguments: %s" % (self._mode,
-                 configuration['mpi'], perf_args))
+            perf("Performance[mode=%s, mpi=%s] arguments: %s, " %
+                 (self._mode, configuration['mpi'], perf_args))
         else:
             perf("Performance[mode=%s] arguments: %s" % (self._mode, perf_args))