Ellsbury (knee) could head out on a rehab assignment as soon as Monday, ESPN New York reports. Manager Joe Girardi said Ellsbury will work out with the team prior to Saturday's game, and if his right knee responds well, the outfielder could be cleared to begin playing in minor league games. It's not entirely clear how long of a rehab assignment Ellsbury will need after missing more than a month with the injury, but a return next weekend seems within the realm of possibility.