Humberto Sanchez is a fairly good prospect. A Dominican who grew up in New York, he was a starter in the Futures Game(the minor league all-star game, basically). He's got potential, if he stays off the DL and away from the buffet line(he's a big boy). Whelan and Claggett are both 2005 draftees and, for the most part, unknowns at this point. Detroit doesn't have a very good farm system, but Sanchez was probably their top pitching prospect.
Assuming Sheffield is healthy, this looks like a pretty good deal for the Tigers. They didn't surrender anything vital to their youth development, and they added another productive bat who, presumably, will be less of a pain than usual under the supervision of fellow Marlins World Series buddies Leyland and Dombroski.
I'm not sure just how healthy Sheffield is, though.
