diff --git a/code/controller/TranslatableCMSMainExtension.php b/code/controller/TranslatableCMSMainExtension.php
index 838cf1a..e7849b3 100644
--- a/code/controller/TranslatableCMSMainExtension.php
+++ b/code/controller/TranslatableCMSMainExtension.php
@@ -9,6 +9,11 @@ class TranslatableCMSMainExtension extends Extension {
 	);
 
 	function init() {
+		// Ignore being called on LeftAndMain base class,
+		// which is the case when requests are first routed through AdminRootController
+		// as an intermediary rather than the endpoint controller
+		if(!$this->owner->stat('tree_class')) return;
+
 		// Locale" attribute is either explicitly added by LeftAndMain Javascript logic,
 		// or implied on a translated record (see {@link Translatable->updateCMSFields()}).
 		// $Lang serves as a "context" which can be inspected by Translatable - hence it