I suspect that by the time I finish writing this the response from fellow HSBBWebbers will be swift enough that this will be just an echo, but here goes....
There is NO WAY that it is appropriate to limit a player who wants to play other posiitions, at least if he has the capability as well as the desire to play them, at the High School level. Probably same response for college, though at that point if the player is receiving a scholarship, obviously the coach should (and does) have more say. At the pro level, the guy writing the checks makes the rules, IMO.
That said, I hate the tendency to put people in a cocoon lest they get injured. Anybody can get injured, doing just about anything in this game, at anytime. Maybe running down warning track shots on a dead run towards the OF fence during While shagging BP is a bad idea - particularly for a 42-year old future HOF closer - but as others have said in the other thread, Rivera was apparently only doing what he had done many times before, a part of his pre-game routine. I guess he just hadn't yet gotten the "slow down, you're in your 40s" memo that most of us get (from our OWN BODIES). IMO, though, that's probably what made him great.
I wouldn't change a thing, other than to tell my pitchers to be smarter about taking unnecessary risks.