diff --git a/mysql-test/lib/mtr_cases.pm b/mysql-test/lib/mtr_cases.pm
index 4d6885f5495..6ec73715a0c 100644
--- a/mysql-test/lib/mtr_cases.pm
+++ b/mysql-test/lib/mtr_cases.pm
@@ -971,7 +971,7 @@ sub envsubst {
 
   if ( ! defined $ENV{$string} )
   {
-    mtr_error("opt file referense \$$string that is unknown");
+    mtr_error(".opt file references '$string' which is not set");
   }
 
   return $ENV{$string};
diff --git a/mysql-test/mysql-test-run.pl b/mysql-test/mysql-test-run.pl
index ce0fe4c8a2b..5bb60d1c9a4 100755
--- a/mysql-test/mysql-test-run.pl
+++ b/mysql-test/mysql-test-run.pl
@@ -388,6 +388,11 @@ sub command_line_setup {
 
   usage("") if $opt_usage;
 
+  # --------------------------------------------------------------------------
+  # Check mtr_build_thread and calculate baseport
+  # --------------------------------------------------------------------------
+  set_mtr_build_thread_ports($opt_mtr_build_thread);
+
   if ( -d "../sql" )
   {
     $source_dist=  1;