diff --git a/src/boot.js b/src/boot.js
index 1d0ad6c..7872858 100644
--- a/src/boot.js
+++ b/src/boot.js
@@ -53,7 +53,8 @@ if (document.readyState === 'complete' || scope.flags.eager) {
 // When loading at other readyStates, wait for the appropriate DOM event to 
 // bootstrap.
 } else {
-  var loadEvent = window.HTMLImports ? 'HTMLImportsLoaded' : 'DOMContentLoaded';
+  var loadEvent = window.HTMLImports && !HTMLImports.ready ?
+      'HTMLImportsLoaded' : 'DOMContentLoaded';
   window.addEventListener(loadEvent, bootstrap);
 }