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15. Deolis Guerra | Starter | DOB: 4/89 | Throws: Right | Trade: Mets
 
YEAR     LV      G     GS      ERA        IP       H     HR      SO     BB
2006     A-     17     17     2.20      81.2      59      3      64     37
2007     A+     21     20     4.01      89.2      80      9      66     25
2008     A+     26     25     5.47     130.0     138     12      71     71

Considered by many to be the highest-upside prospect in the four-player haul that the Twins received for Johan Santana last offseason, Deolis Guerra took a major step backward last year while repeating high Single-A. His strikeout rate declined 33 percent, his walk rate nearly doubled, and he induced 31 percent fewer ground balls while posting an ugly 5.47 ERA and uglier 71-to-71 strikeout-to-walk ratio in 130 innings. And he did all of that in an environment so pitcher-friendly that the league ERA was 3.81.

Guerra's hugely disappointing season can be traced directly to a big drop in velocity, as he spent most of the year in the mid-80s while the Twins tinkered with his mechanics. Between an awful performance and diminished stuff there's no way around the fact that Guerra's stock took a nose dive, but it's also important to remember that he played the entire season at 19 years old. Of the 100 guys in the Florida State League who logged at least 55 innings, Guerra and Rick Porcello were the only teenagers.

The average age of that 100-pitcher group was 23.85, which means that Guerra could spend another three seasons at high Single-A and still be young for the level. None of that will matter unless he gets the lost velocity back and starts living up to some of the hype, but if Guerra had come up through the Twins' system instead of beginning his career with the overly aggressive Mets he may have spent last season facing other teenagers at rookie-ball. His stock is way down, but don't count him out.

14. David Bromberg | Starter | DOB: 9/87 | Throws: Right | Draft: 2005-32
 
YEAR     LV      G     GS      ERA        IP       H     HR      SO     BB
2006     RK-    10     10     2.66      50.2      42      2      31     18
2007     RK     13     11     2.78      58.1      45      4      81     32
2008     A-     27     27     4.44     150.0     149     10     177     54

Selected out of a California high school in the 32nd round of the 2005 draft, David Bromberg signed a year later as a draft-and-follow pick and fared well in the rookie-level Gulf Coast League during his pro debut. He moved up to rookie-level Elizabethton in 2007 and took home Appalachian League pitcher of the year honors by going 9-0 with a 2.78 ERA while leading the league in strikeouts. Bromberg moved up to low Single-A last year for his full-season debut and continued to miss a ton of bats.

In fact, Bromberg led all of minor-league baseball with 177 strikeouts in 150 innings at Beloit and has now whiffed 289 batters in 259.1 career frames. Normally that many strikeouts leads to very few hits because there simply aren't a lot of balls put in play, but Bromberg allowed 149 hits in 150 innings for a .261 opponent's average. He also walked 54, plunked 19, and uncorked 16 wild pitches on the way to a 4.44 ERA that's downright bad in a pitcher-friendly league where the average mark was 3.68.

Of course, it makes sense that a 20-year-old in his first full pro season might struggle to command the type of raw stuff that can rack up 10.6 strikeouts per nine innings. There's plenty of time for Bromberg to harness his stuff and improve his control as he moves up the organizational ladder, but for now he's all strikeouts and upside. Moving up to Fort Myers this season will give the 6-foot-5 right-hander a chance to use his low-90s fastball and big-breaking curveball to lead a third straight league in strikeouts.

13. Carlos Gutierrez | Reliever | DOB: 9/86 | Throws: Right | Draft: 2008-1
 
YEAR     LV      G     GS      ERA        IP       H     HR      SO     BB
2008     A+     16      0     2.10      25.2      23      0      19      7

After taking Aaron Hicks with their own first-round pick in June, the Twins used the Angels' first rounder that they received as compensation for Torii Hunter leaving as a free agent to select University of Miami closer Carlos Gutierrez. Much like Ben Revere the previous year, Gutierrez going 27th overall came as a surprise because most projections had him going several rounds later. Despite that he jumped all the way to high Single-A after signing and pitched well in 16 relief appearances.

Originally a starter at Miami, Gutierrez moved to the bullpen after missing all of 2007 following Tommy John elbow surgery. He came back stronger than ever, posting a 3.02 ERA, 70-to-18 strikeout-to-walk ratio, and .199 opponent's batting average in 48 innings before struggling in the College World Series. Despite making his pro debut as a reliever after closing in college the Twins have indicated that they'll see if Gutierrez can stick as a starter before any full-time move to the bullpen.

He relies heavily on a low-90s sinker, with Baseball America noting that his slider "lacks consistency" and his changeup "is in the rudimentary stages." Because of that Gutierrez would likely need quite a bit of time to work on his secondary pitches before potentially being ready for the majors as a starter, but he could be put on the fast track to Minnesota as a reliever. Gutierrez will go as far as his sinker takes him, and he induced 56 percent ground balls without allowing a homer in his 26-inning debut.

12. Kevin Mulvey | Starter | DOB: 5/85 | Throws: Right | Trade: Mets
 
YEAR     LV      G     GS      ERA        IP       H     HR      SO     BB
2007     AA     26     26     3.32     151.2     145      4     110     43
2008    AAA     27     27     3.77     148.0     152     16     121     48

All three Mets pitching prospects who came to the Twins in the Santana trade took a step backward in 2008, but Kevin Mulvey's decline was at least fairly subtle. Selected in the second round of the 2006 draft after three years at Villanova University, Mulvey jumped right to Double-A and won the Mets' minor league pitcher of the year award. He spent last year at Triple-A following the trade and duplicated his Double-A numbers in most key categories, but saw one major change that dropped his stock.

He tossed 151.2 innings at Double-A and 148 innings at Triple-A, and his strikeouts (110, 121), walks (43, 48), and hits (145, 152) were nearly identical. However, within those similar totals he went from ground-ball pitcher to fly-ball pitcher while serving up four times as many homers. Two years ago he induced a grounder on 55 percent of his balls in play while allowing one homer per 174 batters. Last year he induced a grounder on 40 percent of his balls in play while allowing one homer per 40 batters.

Mulvey basically became a completely different pitcher last year, yet somehow did so while maintaining similar numbers. Unfortunately, going from 55 percent ground balls to 40 percent ground balls is very bad news for a guy who doesn't miss a ton of bats and Mulvey is never going to overpower anyone with his raw stuff. If he can get back to killing worms Mulvey has the potential to be a mid-rotation starter and should be ready for the majors this season. If not, he becomes a pretty marginal prospect.

11. Chris Parmelee | Right Field | DOB: 2/88 | Bats: Left | Draft: 2006-1
 
YEAR     LV      PA      AVG      OBP      SLG     HR    XBH     BB     SO
2006     RK-    179     .279     .369     .532      8     19     23     47
2007     A-     501     .239     .313     .414     15     43     46    137
2008     A-     289     .239     .385     .496     14     27     52     83

Based solely on his .239 batting average you'd conclude that 2006 first-round pick Chris Parmelee had a horrible season, but that's far from the case. Parmelee hitting just .239 last season and .246 for his pro career certainly isn't a good thing and raises questions about his future, but focusing strictly on that overlooks elite power and patience. Angel Morales and Evan Bigley were the only Twins prospects to display more raw power than Parmelee last year and no one in the system had more plate discipline.

To put Parmelee's power in perspective, consider that he played alongside Revere at low Single-A and had an identical slugging percentage despite a huge 140-point gap in the batting average. Unlike most position players in the Twins' system Parmelee has the secondary skills to make a big impact without a big average, but being a poor man's Adam Dunn at Single-A isn't the greatest sign for a prospect's long-term potential given that even Dunn batted .304 in the minors.

Parmelee missed the entire second half of last year with a wrist injury that kept him from approaching 30 homers in a pitcher-friendly league where only three players went deep even 20 times, but even with the missed development time he's still just 21 years old. Wrist injuries can be tricky for a player who derives such a big chunk of his value from power, so 2009 will be crucial for Parmelee's outlook. He's a better prospect than most people think, but still needs to up his batting average to be special.