In one scene when Donald O'Connor finishes talking with Francis in the barn and leaves, Chill Wills is clearly seen standing behind the paddock. He's wearing a cowboy hat and ducks down after he realizes he's on camera. Actually, if you freeze frame that part of the scene, the person ducking out of camera range is clearly not Chill Wills; it's actually Francis'(Who's real name is Molly) trainer Lester L. Hilton.