diff --git a/core/tests/Drupal/Tests/UnitTestCase.php b/core/tests/Drupal/Tests/UnitTestCase.php
index 4561d82..e869b9f 100644
--- a/core/tests/Drupal/Tests/UnitTestCase.php
+++ b/core/tests/Drupal/Tests/UnitTestCase.php
@@ -46,8 +46,10 @@ public static function getInfo() {
    */
   protected function tearDown() {
     parent::tearDown();
-    $container = new ContainerBuilder();
-    \Drupal::setContainer($container);
+    if (\Drupal::getContainer()) {
+      $container = new ContainerBuilder();
+      \Drupal::setContainer($container);
+    }
   }
 
   /**