diff --git a/core/lib/Drupal/Core/Test/EnvironmentCleaner.php b/core/lib/Drupal/Core/Test/EnvironmentCleaner.php
index 15852696..6016bcf4 100644
--- a/core/lib/Drupal/Core/Test/EnvironmentCleaner.php
+++ b/core/lib/Drupal/Core/Test/EnvironmentCleaner.php
@@ -47,7 +47,7 @@ class EnvironmentCleaner implements EnvironmentCleanerInterface {
   protected $output;
 
   /**
-   * Construct an environment cleaner.
+   * Constructs a test environment cleaner.
    *
    * @param string $root
    *   The path to the root of the Drupal installation.
@@ -163,14 +163,8 @@ protected function doCleanTemporaryDirectories() {
   /**
    * {@inheritdoc}
    */
-  public function cleanResults($test_id = NULL) {
-    if ($test_id) {
-      $test_run = TestRun::get($this->testRunResultsStorage, $test_id);
-      return $test_run->removeResults();
-    }
-    else {
-      return $this->testRunResultsStorage->cleanUp();
-    }
+  public function cleanResults(TestRun $test_run = NULL) {
+    return $test_run ? $test_run->removeResults() : $this->testRunResultsStorage->cleanUp();
   }
 
 }
diff --git a/core/lib/Drupal/Core/Test/EnvironmentCleanerInterface.php b/core/lib/Drupal/Core/Test/EnvironmentCleanerInterface.php
index dc5d40cd..e786962c 100644
--- a/core/lib/Drupal/Core/Test/EnvironmentCleanerInterface.php
+++ b/core/lib/Drupal/Core/Test/EnvironmentCleanerInterface.php
@@ -8,11 +8,9 @@
  * This interface is marked internal. It does not imply an API.
  *
  * @todo Formalize this interface in
- *   https://www.drupal.org/project/drupal/issues/3075490 and
- *   https://www.drupal.org/project/drupal/issues/3075608
+ *   https://www.drupal.org/project/drupal/issues/3075490
  *
  * @see https://www.drupal.org/project/drupal/issues/3075490
- * @see https://www.drupal.org/project/drupal/issues/3075608
  *
  * @internal
  */
@@ -25,7 +23,7 @@
    * under test.
    *
    * @param bool $clear_results
-   *   (optional) Whether to clear the test results database. Defaults to TRUE.
+   *   (optional) Whether to clear the test results storage. Defaults to TRUE.
    * @param bool $clear_temp_directories
    *   (optional) Whether to clear the test site directories. Defaults to TRUE.
    * @param bool $clear_database
@@ -46,12 +44,13 @@ public function cleanTemporaryDirectories();
   /**
    * Clears test results from the results storage.
    *
-   * @param $test_id
-   *   Test ID to remove results for, or NULL to remove all results.
+   * @param \Drupal\Core\Test\TestRun $test_run
+   *   The test run object to remove results for, or NULL to remove all
+   *   results.
    *
    * @return int
    *   The number of results that were removed.
    */
-  public function cleanResults($test_id = NULL);
+  public function cleanResults(TestRun $test_run = NULL);
 
 }
diff --git a/core/lib/Drupal/Core/Test/SimpletestTestRunResultsStorage.php b/core/lib/Drupal/Core/Test/SimpletestTestRunResultsStorage.php
index 9780dc33..74486367 100644
--- a/core/lib/Drupal/Core/Test/SimpletestTestRunResultsStorage.php
+++ b/core/lib/Drupal/Core/Test/SimpletestTestRunResultsStorage.php
@@ -100,6 +100,24 @@ public function insertLogEntry(TestRun $test_run, array $entry) {
       ->execute();
   }
 
+  /**
+   * Delete a single log entry by message ID.
+   *
+   * This method is introduced for BC.
+   *
+   * @param $message_id
+   *   Message ID of the log entry to delete.
+   *
+   * @return
+   *   TRUE if the log entry was deleted, FALSE otherwise.
+   */
+  public function removeLogEntry($message_id) {
+    return (bool) $this->connection
+      ->delete('simpletest')
+      ->condition('message_id', $message_id)
+      ->execute();
+  }
+
   /**
    * {@inheritdoc}
    */
diff --git a/core/lib/Drupal/Core/Test/TestSetupTrait.php b/core/lib/Drupal/Core/Test/TestSetupTrait.php
index c7d211e1..0fd7428a 100644
--- a/core/lib/Drupal/Core/Test/TestSetupTrait.php
+++ b/core/lib/Drupal/Core/Test/TestSetupTrait.php
@@ -108,8 +108,14 @@
    *
    * @return \Drupal\Core\Database\Connection
    *   The database connection to use for inserting assertions.
+   *
+   * @deprecated in drupal:x.x.x and is removed from drupal:y.y.y. There is no
+   *   replacement.
+   *
+   * @see https://www.drupal.org/node/xxx
    */
   public static function getDatabaseConnection() {
+    @trigger_error(__METHOD__ . ' in drupal:x.x.x and is removed from drupal:y.y.y. There is no replacement. See https://www.drupal.org/node/xxx', E_USER_DEPRECATED);
     return SimpletestTestRunResultsStorage::getConnection();
   }
 
diff --git a/core/modules/simpletest/simpletest.module b/core/modules/simpletest/simpletest.module
index 9bbb58de..c6e8c14f 100644
--- a/core/modules/simpletest/simpletest.module
+++ b/core/modules/simpletest/simpletest.module
@@ -692,18 +692,19 @@ function simpletest_clean_temporary_directories() {
  *   The number of results that were removed.
  *
  * @deprecated in drupal:8.8.0 and is removed from drupal:9.0.0. Access the
- *   environment_cleaner service and call its cleanResultsTable() method, or use
- *   \Drupal\Core\Test\EnvironmentCleaner::cleanResultsTable() instead.
+ *   environment_cleaner service and call its cleanResults() method, or use
+ *   \Drupal\Core\Test\EnvironmentCleaner::cleanResults() instead.
  *
  * @see https://www.drupal.org/node/3076634
  */
 function simpletest_clean_results_table($test_id = NULL) {
-  @trigger_error(__FUNCTION__ . ' is deprecated in drupal:8.8.0 and is removed from drupal:9.0.0. Access the environment_cleaner service and call its cleanResultsTable() method, or use \Drupal\Core\Test\EnvironmentCleaner::cleanResultsTable() instead. See https://www.drupal.org/node/3076634', E_USER_DEPRECATED);
+  @trigger_error(__FUNCTION__ . ' is deprecated in drupal:8.8.0 and is removed from drupal:9.0.0. Access the environment_cleaner service and call its cleanResults() method, or use \Drupal\Core\Test\EnvironmentCleaner::cleanResults() instead. See https://www.drupal.org/node/3076634', E_USER_DEPRECATED);
   $count = 0;
   if (\Drupal::config('simpletest.settings')->get('clear_results')) {
     /* @var $cleaner \Drupal\simpletest\EnvironmentCleanerService */
     $cleaner = \Drupal::service('environment_cleaner');
-    $count = $cleaner->cleanResults($test_id);
+    $test_run = isset($test_id) ? TestRun::get(new SimpletestTestRunResultsStorage(), $test_id) : NULL;
+    $count = $cleaner->cleanResults($test_run);
   }
   return $count;
 }
diff --git a/core/modules/simpletest/src/Form/SimpletestResultsForm.php b/core/modules/simpletest/src/Form/SimpletestResultsForm.php
index 616caee6..d3c33752 100644
--- a/core/modules/simpletest/src/Form/SimpletestResultsForm.php
+++ b/core/modules/simpletest/src/Form/SimpletestResultsForm.php
@@ -174,7 +174,8 @@ public function buildForm(array $form, FormStateInterface $form_state, $test_id
     ];
 
     if (is_numeric($test_id)) {
-      $this->cleaner->cleanResults($test_id);
+      $test_run = TestRun::get((new SimpletestTestRunResultsStorage($this->database)), $test_id);
+      $this->cleaner->cleanResults($test_run);
     }
 
     return $form;
diff --git a/core/modules/simpletest/src/TestBase.php b/core/modules/simpletest/src/TestBase.php
index 3c456bf8..3d73e626 100644
--- a/core/modules/simpletest/src/TestBase.php
+++ b/core/modules/simpletest/src/TestBase.php
@@ -298,7 +298,7 @@ protected function checkRequirements() {
    *   The message ID.
    */
   protected function storeAssertion(array $assertion) {
-    return TestRun::get(new SimpletestTestRunResultsStorage(self::getDatabaseConnection()), $this->testId)->insertLogEntry($assertion);
+    return TestRun::get(new SimpletestTestRunResultsStorage(), $this->testId)->insertLogEntry($assertion);
   }
 
   /**
@@ -415,7 +415,7 @@ public static function insertAssert($test_id, $test_class, $status, $message = '
     ];
 
     // We can't use storeAssertion() because this method is static.
-    return TestRun::get(new SimpletestTestRunResultsStorage(self::getDatabaseConnection()), $test_id)->insertLogEntry($assertion);
+    return TestRun::get(new SimpletestTestRunResultsStorage(), $test_id)->insertLogEntry($assertion);
   }
 
   /**
@@ -431,10 +431,7 @@ public static function insertAssert($test_id, $test_class, $status, $message = '
    */
   public static function deleteAssert($message_id) {
     // We can't use storeAssertion() because this method is static.
-    return (bool) self::getDatabaseConnection()
-      ->delete('simpletest')
-      ->condition('message_id', $message_id)
-      ->execute();
+    return (new SimpletestTestRunResultsStorage())->removeLogEntry($message_id);
   }
 
   /**
@@ -1037,7 +1034,7 @@ private function prepareDatabasePrefix() {
     // As soon as the database prefix is set, the test might start to execute.
     // All assertions as well as the SimpleTest batch operations are associated
     // with the testId, so the database prefix has to be associated with it.
-    TestRun::get(new SimpletestTestRunResultsStorage(self::getDatabaseConnection()), $this->testId)->setDatabasePrefix($this->databasePrefix);
+    TestRun::get(new SimpletestTestRunResultsStorage(), $this->testId)->setDatabasePrefix($this->databasePrefix);
   }
 
   /**
@@ -1241,7 +1238,7 @@ private function restoreEnvironment() {
 
     // In case a fatal error occurred that was not in the test process read the
     // log to pick up any fatal errors.
-    $test_run = TestRun::get(new SimpletestTestRunResultsStorage(self::getDatabaseConnection()), $this->testId);
+    $test_run = TestRun::get(new SimpletestTestRunResultsStorage(), $this->testId);
     $test_database = new TestDatabase($this->databasePrefix);
     $test_run->processPhpErrorLogFile($test_database->getPhpErrorLogPath(), get_class($this));
 
diff --git a/core/modules/simpletest/tests/src/Kernel/DeprecatedCleanupTest.php b/core/modules/simpletest/tests/src/Kernel/DeprecatedCleanupTest.php
index 0f68cdad..5ed55313 100644
--- a/core/modules/simpletest/tests/src/Kernel/DeprecatedCleanupTest.php
+++ b/core/modules/simpletest/tests/src/Kernel/DeprecatedCleanupTest.php
@@ -4,6 +4,7 @@
 
 use Drupal\Core\DependencyInjection\ContainerBuilder;
 use Drupal\Core\Test\EnvironmentCleanerInterface;
+use Drupal\Core\Test\TestRun;
 use Drupal\KernelTests\KernelTestBase;
 use Symfony\Component\DependencyInjection\Definition;
 
@@ -30,7 +31,7 @@ public function register(ContainerBuilder $container) {
    * @expectedDeprecation simpletest_clean_environment is deprecated in drupal:8.8.0 and is removed from drupal:9.0.0. Access the environment_cleaner service and call its cleanEnvironment() method, or use \Drupal\Core\Test\EnvironmentCleaner::cleanEnvironment() instead.. See https://www.drupal.org/node/3076634
    * @expectedDeprecation simpletest_clean_database is deprecated in drupal:8.8.0 and is removed from drupal:9.0.0. Access the environment_cleaner service and call its cleanDatabase() method, or use \Drupal\Core\Test\EnvironmentCleaner::cleanDatabase() instead. See https://www.drupal.org/node/3076634
    * @expectedDeprecation simpletest_clean_temporary_directories is deprecated in drupal:8.8.0 and is removed from drupal:9.0.0. Access the environment_cleaner service and call its cleanTemporaryDirectories() method, or use \Drupal\Core\Test\EnvironmentCleaner::cleanTemporaryDirectories() instead. See https://www.drupal.org/node/3076634
-   * @expectedDeprecation simpletest_clean_results_table is deprecated in drupal:8.8.0 and is removed from drupal:9.0.0. Access the environment_cleaner service and call its cleanResultsTable() method, or use \Drupal\Core\Test\EnvironmentCleaner::cleanResultsTable() instead. See https://www.drupal.org/node/3076634
+   * @expectedDeprecation simpletest_clean_results_table is deprecated in drupal:8.8.0 and is removed from drupal:9.0.0. Access the environment_cleaner service and call its cleanResults() method, or use \Drupal\Core\Test\EnvironmentCleaner::cleanResults() instead. See https://www.drupal.org/node/3076634
    */
   public function testDeprecatedCleanFunctions() {
     $this->assertNull(simpletest_clean_environment());
@@ -54,7 +55,7 @@ public function cleanEnvironment($clear_results = TRUE, $clear_temp_directories
 
   }
 
-  public function cleanResults($test_id = NULL) {
+  public function cleanResults(TestRun $test_run = NULL) {
 
   }
 
diff --git a/core/tests/Drupal/KernelTests/Core/Test/TestSetupTraitTest.php b/core/tests/Drupal/KernelTests/Core/Test/TestSetupTraitTest.php
new file mode 100644
index 00000000..e6875687
--- /dev/null
+++ b/core/tests/Drupal/KernelTests/Core/Test/TestSetupTraitTest.php
@@ -0,0 +1,32 @@
+<?php
+
+namespace Drupal\KernelTests\Core\Test;
+
+use Drupal\Core\Test\TestSetupTrait;
+use Drupal\KernelTests\KernelTestBase;
+
+/**
+ * Tests the TestSetupTrait trait.
+ *
+ * @coversDefaultClass \Drupal\Core\Test\TestSetupTrait
+ * @group Testing
+ *
+ * Run in a separate process as this test involves Database statics and
+ * environment variables.
+ * @runTestsInSeparateProcesses
+ * @preserveGlobalState disabled
+ */
+class TestSetupTraitTest extends KernelTestBase {
+
+  use TestSetupTrait;
+
+  /**
+   * @covers ::getDatabaseConnection
+   * @group legacy
+   * @expectedDeprecation Drupal\Core\Test\TestSetupTrait::getDatabaseConnection in drupal:x.x.x and is removed from drupal:y.y.y. There is no replacement. See https://www.drupal.org/node/xxx
+   */
+  public function testGetDatabaseConnection() {
+    $this->assertNotNull($this->getDatabaseConnection());
+  }
+
+}