diff --git a/core/modules/migrate/src/Plugin/migrate/process/Route.php b/core/modules/migrate/src/Plugin/migrate/process/Route.php
index ff04a52..4e42774 100644
--- a/core/modules/migrate/src/Plugin/migrate/process/Route.php
+++ b/core/modules/migrate/src/Plugin/migrate/process/Route.php
@@ -80,7 +80,7 @@ public function transform($value, MigrateExecutableInterface $migrate_executable
           $options['query'] = $route['options']['query'] + $old_query;
           unset($route['options']['query']);
         }
-        $route['options'] = $route['options'] + $options;
+        $route['options'] = array_merge($route['options'], $options);
         $route['url'] = NULL;
       }
     }