diff -u b/tests/src/Kernel/CrudTest.php b/tests/src/Kernel/CrudTest.php
--- b/tests/src/Kernel/CrudTest.php
+++ b/tests/src/Kernel/CrudTest.php
@@ -240,7 +240,7 @@
     $job->save();
     $job_item = tmgmt_job_item_create('test_source', 'test_type', 1, ['tjid' => $job->id()]);
     $job_item->save();
-    $job_item->updateData('title', [0 => ['value' => ['#translation' => ['#text' => 'Invalid translation that will cause an exception']]]], TRUE);
+    $job_item->updateData(['dummy', 'deep_nesting'], ['#text' => 'Invalid translation that will cause an exception']);
     $job_item->save();
 
     // Request translation. Here it fails.
diff -u b/tmgmt_test/src/Plugin/tmgmt/Source/TestSource.php b/tmgmt_test/src/Plugin/tmgmt/Source/TestSource.php
--- b/tmgmt_test/src/Plugin/tmgmt/Source/TestSource.php
+++ b/tmgmt_test/src/Plugin/tmgmt/Source/TestSource.php
@@ -101,7 +101,7 @@
   public function saveTranslation(JobItemInterface $job_item, $target_langcode) {
     // Set a variable that can be checked later for a given job item.
     $data = $job_item->getData();
-    if (isset($data['title'][0]['value']['#translation']['#text']) && $data['title'][0]['value']['#translation']['#text'] == 'Invalid translation that will cause an exception') {
+    if (isset($data['dummy']['deep_nesting']['#text']) && $data['dummy']['deep_nesting']['#text'] == 'Invalid translation that will cause an exception') {
       throw new \Exception('The translation cannot be saved.');
     }
     \Drupal::state()->set('tmgmt_test_saved_translation_' . $job_item->getItemType() . '_' . $job_item->getItemId(), $job_item->getData());