Castro may even be the best young shortstop in the game. Doubt it? Try naming one better. Even with a prolonged slump in 2012, he still posted a .283 batting average, hit 14 home runs and 12 triples, and 78 runs. He ranked seventh among shortstops in batting average - no one above him was younger. He led all shortstops in RBI (78) and triples (tied at 12 with Jose Reyes), and was third among shortstops in hits (183). Remember, this is a 22 year-old who has consistently produced at the major league level. Guys like that don't come around often.
Starlin does have his problems though. A perceived lack of effort and concentration has led to a position-leading 27 errors in 2012. Asdrubal Cabrera, who was second in shortstop errors, wasn't even close (19). Castro still has problems with plate discipline as well - his strikeouts have increased and his on-base percentage has deceased each year he has been in the majors. He only walked 36 times in a league-leading 646 at bats in 2012. He isn't polished by any means.
If the Cubs trust that Baez will eventually be ready to step in as the Cubs' everyday shortstop, will they be willing to trade Starlin? Castro recently signed a seven year, $60 million dollar deal, which means some teams will automatically be out of any possible deal, but other teams will jump at the chance to acquire a good shortstop at a relatively affordable price. If the Cubs can find the right player to target - say, Justin Upton of the Diamondbacks - Theo Epstein and Jed Hoyer must seriously consider making a move. Losing Castro may be unpopular with some fans, but pulling the trigger on a deal could lead to a more competitive Cubs team.