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Also in this series: 1-5, 6-10, 11-15, 16-20, 26-30, 31-35, 36-40.

25. Carlos Gutierrez | Reliever | DOB: 9/86 | Throws: Right | Draft: 2008-1

YEAR     LV      G     GS      ERA        IP       H     HR      SO     BB
2009     A+     11     10     1.32      54.2      37      1      33     22
         AA     22      6     6.19      52.1      62      6      32     24
2010     AA     32     16     4.57     122.0     136      7      81     50
2011     AAA    43      0     4.62      62.1      60      2      57     31

From the moment they took him 27th overall in the 2008 draft the Twins have talked up Carlos Gutierrez as a future late-inning reliever, touting his "power sinker" and closing experience at the University of Miami. Unfortunately there hasn't been much about his actual performance to match those high hopes, as his impressive ground-ball rate comes attached to terrible control, just 6.4 strikeouts per nine innings, and a 4.07 ERA in four pro seasons.

Gutierrez missed more bats at Triple-A last season, but 57 strikeouts over 62 innings is hardly encouraging for a 24-year-old reliever with high-leverage aspirations, and his control actually regressed with 4.5 walks per nine innings. When he threw the ball over the plate Gutierrez's sinker did its job, as he allowed just two homers and induced 62 percent ground balls. To put that in some context, Jake Westbrook led the majors in grounders last season at 60 percent.

Throwing hard and inducing 60 percent ground balls is enough to make Gutierrez a future big leaguer, but without more missed bats or dramatically improved control it's currently difficult to envision him as a successful setup man or closer. At age 25 he's running out of time to turn his raw stuff into results, but Gutierrez will likely begin this season back in Rochester and figures to crack the Twins' bullpen at some point.

24. Nate Roberts | Left Field | DOB: 2/89 | Bats: Left | Draft: 2010-5

YEAR     LV      PA      AVG      OBP      SLG     HR    XBH     BB     SO
2010     RK+    153     .336     .444     .547      5     16     21     29
2011     A-     283     .302     .443     .446      4     20     28     48

Knee problems limited Nate Roberts to 68 games last year in his full-season debut at low Single-A, but when healthy he showed the exceptional on-base skills that allowed him to lead the country in on-base percentage as a junior at High Point University. Roberts won Big South conference player of the year by hitting .417 with 19 homers, 36 steals, and a ridiculous .573 OBP, which got him selected by the Twins in the fifth round.

Roberts hit .336 with a .444 OBP in his 35-game debut at rookie-ball after signing and then batted .302 with a .443 OBP in Beloit last season. In addition to a combined .314 batting average and 49 walks in 436 plate appearances he's also been hit by 33 pitches, which is a total high enough to seem like a fluke if not for the fact that Roberts was plunked 25 times in just 56 games for High Point in 2010.

Getting hit by pitches is definitely a skill, and players like Craig Biggio, Carlos Quentin, Jason Kendall, and Chase Utley boost their on-base percentages by routinely getting plunked 20-plus times per season. Along with the high batting average, solid walk rate, and plus speed that makes Roberts an underrated prospect, but he's too old to be stuck in the low minors much longer and as a corner outfielder he'll need to develop more power than he's shown.

23. Matthew Summers | Reliever | DOB: 8/89 | Throws: Right | Draft: 2011-4

YEAR     LV      G     GS      ERA        IP       H     HR      SO     BB
2011     RK+    20      0     0.87      20.2      11      0      36      5

Matthew Summers began his college career as an outfielder, but moved to the mound full time last season and became UC-Irvine's best starter, throwing 116 innings with a 2.02 ERA and 99-to-32 strikeout-to-walk ratio while allowing just one homer. That got him a $172,000 signing bonus as the Twins' fourth-round pick and Summers predictably dominated rookie-ball hitters in his pro debut.

Working out of the bullpen in Elizabethton he posted a 0.87 ERA and 36-to-5 strikeout-to-walk ratio in 21 innings, allowing no homers and inducing 57 percent ground balls while opponents hit just .153 off him. Letting college pitchers toy with rookie-ball hitters is standard operating procedure for the Twins and typically doesn't mean much, but in Summers' case his own lack of experience as a pitcher at least made it more of a fair fight.

His long-term role is unclear, as Baseball America reports that he works in the low-90s as a starter and the mid-90s as a reliever. He also has the unorthodox delivery and rudimentary off-speed pitches of a former position player, so the 6-foot-1 right-hander may be destined for the bullpen despite winning Big West conference pitcher of the year honors as a starter. Regardless of the role, Summers will make his full-season debut this year.

22. Tom Stuifbergen | Starter | DOB: 9/88 | Throws: Right | Sign: Netherlands

YEAR     LV      G     GS      ERA        IP       H     HR      SO     BB
2009     RK+    13     13     3.28      79.2      79      4      69      6
2010     A-     19     17     2.98      93.2      99      5      88     23
2011     A+     23     22     4.40     116.2     151     10      75     19

Tom Stuifbergen signed with the Twins out of the Netherlands as an 18-year-old in 2006, missed all of 2008 following shoulder surgery, and missed time with elbow problems in 2009 and 2010, but he's still managed to establish himself as a solid prospect and potential mid-rotation starter. Long term his success may hinge on inducing ground balls in bunches, however, because Stuifbergen's strikeout rate plummeted while stepping up to high Single-A.

His strikeout-to-walk ratio remained excellent in Fort Myers, but that was mostly due to just 1.5 walks per nine innings. His strikeout rate fell from 8.5 per nine innings to 5.6 per nine innings, and he also served up 11 homers in 117 frames after allowing a total of just nine career homers in 189 innings coming into the year. And while his sinker kills plenty of worms, his ground-ball rate of 47 percent during the past two seasons isn't anything special.

Stuifbergen has pitched well in international competition, including thriving on a big stage in 2009 while being coached by Bert Blyleven in the World Baseball Classic. Last year in this space I compared Stuifbergen to Nick Blackburn and that still looks pretty accurate. Blackburn logged 131 innings in Fort Myers, striking out 76 and walking 23 with a 4.19 ERA. Stuifbergen has thrown 119 innings in Fort Myers, striking out 78 and walking 20 with a 4.53 ERA.

21. David Bromberg | Starter | DOB: 9/87 | Throws: Right | Draft: 2005-32

YEAR     LV      G     GS      ERA        IP       H     HR      SO     BB
2009     A+     27     26     2.70     153.1     125      6     148     63
2010     AA     17     17     3.62      99.1     105      4      65     35
         AAA     9      9     3.98      52.0      47      9      47     13
2011     AA      8      7     6.08      37.0      50      3      23     15

David Bromberg led his league in strikeouts in 2007, 2008, and 2009, the latter of which got him named Twins minor league pitcher of the year, but his performance dropped off while making the jump to Double-A in 2010 and he missed most of last season when a line drive broke his forearm. Between the injury and struggles his stock dropped so far in such a short time that the Twins trimmed him from the 40-man roster and no team claimed him off waivers.

That doesn't mean Bromberg won't go on to have a big-league career, but it does suggest that his perceived upside isn't strong and most teams don't view him as being MLB-ready. He's still just 24 years old and Bromberg can be given a pass for getting knocked around after the injury, but even before last season his strikeouts per nine innings had plummeted from 10.6 to 8.7 to 6.7 and he's totaled just 137 strikeouts in 188 innings above Single-A.

Bromberg is 6-foot-5 and hefty even after dropping 30 pounds last year and some more weight this winter, but his fastball tops out in the low-90s. His off-speed stuff gets positive reviews and prior to being derailed by the broken forearm he'd sliced his walk rate from poor to mediocre, but as a fly-ball pitcher who doesn't seem likely to miss many bats his upside is limited. He's capable of being a mid-rotation starter, but this year will be key for his chances.