Is he still club captain? If so he would, presumably, be in the dressing room for each game. IMHO I think he should be on the bench in case of injuries or someone having "a mare". He would still be an influence and I'm sure there are ways of warming up if he needs too. Why not take a static bike to the dugout? He could limber up on that before the obligatory stretching exercises and running up and down the side line.