The Cubs have 22 year old Starlin Castro manning shortstop for the foreseeable future. They also have high profile prospects Junior Lake and Javier Baez currently playing the position.
But the player with the best hope of someday moving Castro to 3B or 2B is a 19 year old SS named Marco Hernandez. Hernandez is a 6’0, 170 lbs, switch-hitting prospect who signed out of the Dominican Republic in 2009.
He’s athletic and posseses both above-average speed and quickness, which give him plenty of range at short to go with his strong arm. He has solid tools across the board and, unlike Baez, doesn’t figure to outgrow the position. Baez has a projectable frame and that has most thinking he’ll eventually need to move to 3B or perhaps the OF. Lake may have already outgrown shortstop and at any rate doesn't possess the same defensive ability as Castro. If Lake and/or Baez make it to the big leagues, they'll be the ones that will change position. That may not be the case with Hernandez.
In addition to being a legit SS defensively, Hernandez has a pretty good bat. A line drive stroke helps him make plenty of contact and he figures to hit for average from both sides of the plate, though he's better from the left side. His smaller frame doesn’t portend many HRs down the line but he figures to have some extra base power. His above average speed could be an asset on the bases as he better learns the nuances of baserunning. Last year at Rookie Level Arizona, Hernandez put up a line of 333/.375/.486.
Jason McLeod stated that there were about a half dozen surprises in camp and I've specifically mentioned RHP Ben Wells as one of those players, but I believe Hernandez is in this group as well. At the very least, the Cubs were impressed enough with his performance in camp to have him skip short-season Boise. He'll start the year with the Peoria Chiefs while the more highly touted Baez stays behind in extended spring training. It's a big step-up in terms of the talent he'll face, but I asked Baseball Prospectus prospect guru Kevin Goldstein via Twitter if he thought Hernandez could handle the leap from the rookie league to full season A ball and his response was yes.
If he does, that would put Hernandez on track to reach Chicago by about 2015 when he’ll be about 22 years old. By then Castro will be at the ripe old age of 25 and the Cubs will likely have made a decision by then if he will be the team’s long term solution at SS.
For the record, I think Castro sticks at SS, at least for the next 5-6 years. He has the actions and arm to play there and I believe the better coaching will help him cut down on the mental mistakes and errors. However, if there is any prospect would could one day move him to 3B, it’s not going to be high profile guys like Lake and Baez, it'll be Marco Hernandez.