1. Nolan Arenado, 3B, 21
Many people (in the industry and otherwise) expected this Spring that Arenado would chew up Double-A pitchers much like he did during the Arizona Fall League and he'd be manning the hot corner in Colorado by midseason. Unfortunately, he isn't tearing the cover off of anything in Tulsa and it turns out there's a reason for Double-A. He's hitting .292 with six home runs and a .136 ISO in 68 games. That's not terrible, but he's showing the drawbacks of a player who derives almost all of his value from his bat without hitting for great power. At sea level, he's human in the power department and he won't get to Coors Field until we see more from the stick. He could work on his speed too as he leads the Drillers in double plays with nine.
2. David Dahl, OF, 18
Dahl projects as a speedy outfielder that'll be an asset in the field, likely in center, at the plate, and on the bases. Dahl impressed the Rockies brass at his pre-draft workout held at Coors Field, where he showed off a personal best in the forty yard dash. He possesses the potential for above average to plus tools across the board and he's currently the only player in this system who that can be said about without outright lying. So, that's why I have him ranked this high. Now, a lot can go wrong with a player this young, but Dahl is not just potential and projection. His present speed and raw power could be serious difference makers down the line. Scouts that saw him hit against good competition with wood bats are sold on his hit tool and the Rockies were very happy he made it all the way to number 10 in the draft.
3. Trevor Story, SS, 19
Story's numbers with Asheville right now are ridiculous. A .266/.361/.506 line is not what we're going to see from him when he gets to the big leagues, but it's exciting nonetheless to see a player like him doing this. Story is an all-out player who is getting the most out of his abilities. He's a player that's impossible not to like as he is at least solid in all aspects of the game, just don't expect him to SLG .500 in the majors.
4. Will Swanner, C, 20
Swanner could be the Rockies catcher of the future, but he's still a long way off as he's a fairly raw prospect. Behind the plate, he has a lot of work to do on his receiving and carries merely a solid-average throwing arm. At the plate, he's got power for days but his long swing and lack of pitch recognition give scouts some pause. The only thing that's certain right now for Swanner is that it will take time, but the ceiling is there and that's pretty important.
5. Tyler Matzek, LHP, 21
The 11th overall pick in the 2009 Draft, Matzek has seen his stock drop and comeback again and again as he's seemingly only as good as the number of days since he last walked six batters in an outing. He's walked only four batters in his last two starts (13 IP) while also recording 13 strikeouts, but he walked eight in the start before those starts. Matzek has walked 52 in 75 innings (6.2 BB/9) and getting his star to shine will be all about the development of his delivery and command. If he does, scouts like his stuff when he's on as his arsenal features a fastball in the mid-90's, a curveball, and a slider. The changeup remains a work in progress, but then again so is Matzek, who was so out of control last year he left the Rockies to work on his mechanics with his high school coach. He's returned and so has his ceiling.
6. Chad Bettis, RHP, 23
Bettis hasn't pitched all season due to shoulder woes that showed up early in Spring. The Rockies shut him down and his return is still at least a few weeks away. However, assuming he's able to get back on the mound, Bettis is still a prospect to watch. For an organization absolutely starving for upside arms, Bettis' fastball and slider combination fit the bill. Both pitches profile as plus, but there are remaining questions about his changeup, his viability in the rotation, and his health. If he can at least stay healthy, the worst case scenario is a strong late inning reliever.
7. Corey Dickerson, OF, 23
Dickerson has raked at every stop since the Rockies drafted him in the 8th round in 2010 and even his first few games at Double-A have been that way as he hit a home run in his first game there. He also has some speed to burn in the outfield and on the bases, but the power in his bat is always going to be Dickerson's calling card.
8. Tyler Anderson, LHP, 22
Anderson has done a fine job with Asheville so far. He's made seven starts and despite the lack of a lot of strikeouts (15.3% K%), he's been exceptional at getting outs (1.08 WHIP). Anderson, who went to Oregon, is fairly polished so a promotion to High-A Modesto sometime this year isn't out of the question.
9. Josh Rutledge, SS, 23
Rutledge is excelling at Double-A this season. Drafted in the third round of the 2010 Draft out of Alabama, he showed a nice swing and the ability to make solid contact with gap power at High-A in 2011 (he hit .348 with nine home runs in 113 games). This year, more of the same. Rutledge is hitting .302 with nine home runs in 67 games. He doesn't project to be much of a power hitter down the line, possible 10 home runs and 10+ steals upside. He also doesn't project as a shortstop and that has nothing to do with Troy Tulowitzki. He could be a solid everyday second basemen and those don't grow on trees these days.
10. Tim Wheeler, OF, 24
Wheeler broke out last year with 33 home runs at Double-A, but he suffered a major set back early this year as he broke his right hamate bone. Predictably, upon return Wheeler has been sapped of his power as he has zero home runs and eight doubles in 21 games for Triple-A Colorado Springs. He's been crushing it in his last 10 games, however, as he's hitting .381 (16-for-42) with five doubles.