diff --git a/test/lib/test/unit.rb b/test/lib/test/unit.rb
index f588aec551..105a9a897d 100644
--- a/test/lib/test/unit.rb
+++ b/test/lib/test/unit.rb
@@ -404,7 +404,7 @@ module Test
           end
           if @options[:separate] and not bang
             worker.quit
-            worker = add_worker
+            worker = launch_worker
           end
           worker.run(task, type)
           @test_count += 1
diff --git a/test/testunit/test_parallel.rb b/test/testunit/test_parallel.rb
index 89b5bfa50b..b11330b46d 100644
--- a/test/testunit/test_parallel.rb
+++ b/test/testunit/test_parallel.rb
@@ -195,7 +195,8 @@ module TestParallel
       # this test depends to --jobs-status
       spawn_runner "--jobs-status", "--separate"
       buf = Timeout.timeout(TIMEOUT) {@test_out.read}
-      assert(buf.scan(/(\d+?)[:=]/).flatten.uniq.size > 1)
+      assert(buf.scan(/^\[\s*\d+\/\d+\]\s*(\d+?)=/).flatten.uniq.size > 1,
+             message("retried tests should run in different processes") {buf})
     end
   end
 end