Summary
A tall, projectable infielder, Castellanos may be one of the best high school bats in this draft class. He played shortstop in high school, but his size (he's a long-limbed 6'4") limits his agility and means he'll likely move to third base as a pro. His best tools are his raw, projectable power and his clean, simple swing.
Floor
As a young high school hitter, Castellanos is lanky and will need to bulk up and improve his approach at the plate. His swing is already clean and he's shown the ability to hit the ball to all fields, but he's a long way from his ceiling as a hitter. He's far from being the biggest gamble in this draft class, but he does need some projection to become an impact bat in the big leagues. His defense should play fine at the hot corner; it's not and will likely never be a plus, but he's already average, and should remain so even as he matures.
Ceiling
Many scouts believe that Castellanos has a very high ceiling as a hitter, perhaps even star, 30+ homer potential. His swing is clean and adjustable, he gets good leverage, and he has plenty of room on his frame for additional bulk. He has a chance to hit for both average and power, and runs surprisingly well for his size.
College Commitment
University of Miami
Will the Astros pick him? If so, where?
Because I've read that he's demanding a large signing bonus, my take is no, they won't, not unless they've really fallen in love with his bat. The Astros have three of the first thirty-three picks to pay for, and they're never big spenders in the draft under Drayton McLane. Most believe that his signability issues have tanked his draft stock, but on pure talent, he wouldn't be much of a reach at #8. Most likely he'll still be there at #19, and will fall to one of the big-spending teams (like the Red Sox) in the late first round picks.
Where is he projected to go right now?
Andy Seiler has him at No. 20 in his latest mock draft, going to the Red Sox.
Deep Leagues has him going No. 15 to the Rangers.
Frankie Piliere has him going No. 24 to the Giants.
Jonathan Mayo has him going No. 14 to the Brewers.
Keith Law has him going No. 14 to the Brewers.
Perfect Game USA has him going No. 20 to the Red Sox.
Baseball America has him going No. 24 to the Giants.
Bibliography (Scouting Reports and video)
Below the jump.
Lincoln Hamilton's take, ranked No. 4 overall:
Best pure hitter in draft, plus power potential, will outgrow SS but solid defender at 3B, strong arm
Nick Castellanos is a power-hitting high school shortstop who'll likely change positions as soon as he gets into pro ball; his calling card is his bat, and it'll play at third base, which is his most likely destination as well.
Castellanos has very strong hands and wrists, so even though he still has an 18-year-old's build, he can generate power now, especially with a metal bat. His front side can be a little soft and he doesn't completely close it on most swings. He's athletic for his size but isn't a plus runner.
He's already big for shortstop, but is athletic enough to play it at the high school level; I imagine the team that drafts him will send him right to third base, where he should be above-average. He's going to hit enough to play there, probably enough to profile in an outfield corner if that ever became necessary, with the ability to hit for average and power when he reaches his mid-20s.