If Sheets gets hit by a pitch, should Ned yank him from the game? It may be sore and bruised, and he might altar his pitching motion and hurt his arm. As long as the player and trainer say they are fine, you keep them out there. Then, the manager, pitching coach, and others keep a close eye on them to make sure that their motion isn't being altared/hindered. Exactly what they did yesterday. Same thing 99% of the managers in MLB would do.