diff --git a/storage/innobase/trx/trx0trx.cc b/storage/innobase/trx/trx0trx.cc
index 29a5a9be1a9..a98be51375f 100644
--- a/storage/innobase/trx/trx0trx.cc
+++ b/storage/innobase/trx/trx0trx.cc
@@ -1489,12 +1489,12 @@ static bool trx_serialisation_number_get(
       elem.insert(temp_rseg);
     }
 
-    mutex_enter(&purge_sys->pq_mutex);
-
     added_trx_no = trx_add_to_serialisation_list(trx);
 
     elem.set_trx_no(trx->no);
 
+    mutex_enter(&purge_sys->pq_mutex);
+
     purge_sys->purge_queue->push(std::move(elem));
 
     mutex_exit(&purge_sys->pq_mutex);