It's. Not. About. The. Stats.
Except for possession and accuracy. Xavi's primary role is *not* to create, but to get the ball up the field to the creators, and provide a safe outlet for the creators.
It's hard to judge how ManCity will play. If they play an open game, Xavi will keep them running in circles, and plenty of room for the Barça attack. If they sit back and wait for the ball, then Xavi's skills aren't as needed.
My guess is that Xavi will start, as both teams will be more conservative starting out, trying to feel the other team. If Man City sits back, Xavi will be subbed off at 60.