diff --git a/lib/cast/cast_utils.js b/lib/cast/cast_utils.js
index fade3dce79..2bd8f93e79 100644
--- a/lib/cast/cast_utils.js
+++ b/lib/cast/cast_utils.js
@@ -305,6 +305,7 @@ shaka.cast.CastUtils.PlayerGetterMethods = {
   'getAssetUri': 2,
   'getAudioLanguages': 4,
   'getAudioLanguagesAndRoles': 4,
+  'getBufferFullness': 1,
   'getBufferedInfo': 2,
   // NOTE: The 'getSharedConfiguration' property is not proxied as it would
   //       not be possible to share a reference.