diff --git a/mod/quiz/classes/external/submit_question_version.php b/mod/quiz/classes/external/submit_question_version.php
index e640f98849afe..bc6a4da841e87 100644
--- a/mod/quiz/classes/external/submit_question_version.php
+++ b/mod/quiz/classes/external/submit_question_version.php
@@ -28,8 +28,6 @@
 use core_external\external_single_structure;
 use core_external\external_value;
 use mod_quiz\quiz_settings;
-use mod_quiz\structure;
-use stdClass;
 
 /**
  * External api for changing the question version in the quiz.
diff --git a/mod/quiz/tests/event/events_test.php b/mod/quiz/tests/event/events_test.php
index a13a48dbc3919..381e5139cd6ae 100644
--- a/mod/quiz/tests/event/events_test.php
+++ b/mod/quiz/tests/event/events_test.php
@@ -28,6 +28,7 @@
 use mod_quiz\quiz_attempt;
 use mod_quiz\quiz_settings;
 use context_module;
+use mod_quiz\external\submit_question_version;
 
 /**
  * Unit tests for quiz events.
@@ -68,6 +69,10 @@ protected function prepare_quiz() {
         $saq = $questiongenerator->create_question('shortanswer', null, ['category' => $cat->id]);
         $numq = $questiongenerator->create_question('numerical', null, ['category' => $cat->id]);
 
+        // Update the numq question so it has multiple versions. Needed to test
+        // the version updated event.
+        $questiongenerator->update_question($numq, null, ['name' => 'Second version of numq']);
+
         // Add them to the quiz.
         quiz_add_quiz_question($saq->id, $quiz);
         quiz_add_quiz_question($numq->id, $quiz);
@@ -1202,6 +1207,29 @@ public function test_slot_mark_updated(): void {
         $this->assertEventContextNotUsed($event);
     }
 
+    /**
+     * Test the slot version updated event.
+     *
+     * @covers \mod_quiz\external\submit_question_version
+     */
+    public function test_slot_version_updated(): void {
+        $quizobj = $this->prepare_quiz();
+        $this->setAdminUser();
+
+        $quizobj->preload_questions();
+        [, $numqslotid] = array_column($quizobj->get_questions(null, false), 'slotid');
+
+        $sink = $this->redirectEvents();
+        submit_question_version::execute($numqslotid, 2);
+        $events = $sink->get_events();
+        $event = reset($events);
+
+        // Check that the event data is valid.
+        $this->assertInstanceOf('\mod_quiz\event\slot_version_updated', $event);
+        $this->assertEquals($quizobj->get_context(), $event->get_context());
+        $this->assertEventContextNotUsed($event);
+    }
+
     /**
      * Test quiz_grade_item_created.
      *