Back when the Cubs were struggling in April, I made a snarky comment on Twitter expecting some kind of over-reaction from the front office.  To be honest, I expected the Cubs to call up the red-hot Starlin Castro then, but instead, they decided to create baseball's first $18 million mop-up reliever.  A mid-week sweep by the lowly Pirates brought another need for a move, and today, the Cubs finally did call up Castro, who by going 10-for-17 in his last four games had raised his triple-slash line at Double-A Tennessee to a more-than-impressive .376/.421/.569.  The Dominican shortstop just turned 20 in March, but after a monster spring and this much offense so far in the Southern League, I think we can have some confidence that he's going to hit immediately.  Certainly not .376, but he should hold his own, as in yesterday's Scouting Notebook, a scout believed he could be a future 70 hitter, which is nearly batting title territory.  Beyond the ability to hammer line drives all over the field, Castro has a good, not great approach, but he's not overly aggressive like Corey Patterson was, and it shouldn't be a problem in the big leagues. 

The one thing to keep in mind however is the massive expectations Castro's mere existence have created for many Cubs fans.  He is not a typical 20-year-old Dominican shortstop.  He's not some sort of massive tools monster.  He's a fantastic hitter, but he's speed is average, and he power is still a long way from being of the in-game variety.  In 995 professional at-bats, he has nine career home runs, including just one this year, so while many project double-digit, if not more power down the road, don't expect it now.  In fact, by the time it does come, he's thickening body may have gotten to the point where he's no longer a shortstop.  He's not a do-it-all player as much as he is a solid defender and very good hitter.  One front-office official might have put it best when he said, "he's more Yunel Escobar than Jose Reyes."

That's not to say Castro can't help, and help immediately.  He makes the Cubs better right now.  While the sliding of Ryan Theriot to second base, the team gets better overall offensively, while improving defensively at two positions.  Even with just average wheels, he brings speed (how many even average runners do the Cubs have?) and energy to a lineup that is in desperate need of both, and I see little reason to believe he can't hit somewhere between his 70th and 80th percentile PECOTA forecasts with a line of .275/.335/.410.