diff --git a/src/components/sidenav/sidenav.ts b/src/components/sidenav/sidenav.ts
index db2a9dc35223..295e60486b9a 100644
--- a/src/components/sidenav/sidenav.ts
+++ b/src/components/sidenav/sidenav.ts
@@ -102,7 +102,7 @@ export class MdSidenav {
     // Shortcut it if we're already opened.
     if (isOpen === this.opened) {
       if (!this._transition) {
-        return Promise.resolve();
+        return Promise.resolve(null);
       } else {
         return isOpen ? this._openPromise : this._closePromise;
       }