diff --git a/src/api/z3_replayer.cpp b/src/api/z3_replayer.cpp
index 079516145..acdb10bf6 100644
--- a/src/api/z3_replayer.cpp
+++ b/src/api/z3_replayer.cpp
@@ -26,6 +26,7 @@ Notes:
 void register_z3_replayer_cmds(z3_replayer & in);
 
 void throw_invalid_reference() {
+    TRACE("z3_replayer", tout << "invalid argument reference\n";);
     throw z3_replayer_exception("invalid argument reference");
 }