The fact that it's so unprecedented would make me even less likely to project a rebound. Guys who had a drop of 200 points or more on OPS over their previous ~800 PAs or so and then had a full season the next year after the big drop. There are 87 such guys from 1900-2006. On average they recovered 60% of their lost OPS. I made no restraints on age. A majority of the players seem to be guys at the end of their careers. Most of the guys that have a longer history of production gained more of it, obviously, when they weren't old. Quite an impressive list though. Babe Ruth (x2), Nap Lajoie, Rogers Hornsby, Max Carey, Bill Nicholson, Roy Campanella, Hack Wilson, Jakie Robinson, Al Rosen, Frank Robinson (x2), Will McCovey (x2), Elston Howard, Jimmy Wynn, George Scott, Dick Allen, Hank Aaron, Joe Morgan, Ted Simmons (x2), Fred Lynn, Reggie Jackson (x2), Jeff Burroughs, Bill Madlock, Alan Trammell, Ken Griffey Jr, Gary Sheffield, Albert Belle, Frank Thomas, Larry Walker, Jason Giambi and of course Corey Patterson. It really is quite a list. Even if he gains back 60%, as expected, that's going to be in the 740-50 range for his OPS. Given the fact that most of these guys were on the tail end of their career, I would suspect him to gain more of that back since he was 29 and has a decent length of production than what I have used.