diff --git a/core/tests/bootstrap.php b/core/tests/bootstrap.php
index 5309f1a..9aeb1d7 100644
--- a/core/tests/bootstrap.php
+++ b/core/tests/bootstrap.php
@@ -117,7 +117,6 @@ function drupal_phpunit_populate_class_loader() {
   $loader->add('Drupal\\KernelTests', __DIR__);
   $loader->add('Drupal\\FunctionalTests', __DIR__);
   $loader->add('Drupal\\FunctionalJavascriptTests', __DIR__);
-  $loader->add('Drupal\\TestSuites', __DIR__);
 
   if (!isset($GLOBALS['namespaces'])) {
     // Scan for arbitrary extension namespaces from core and contrib.