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

25. 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
2012     A-     352     .299     .433     .427      4     25     44     37

Nate Roberts has moved very slowly through the system since being drafted in the fifth round out of High Point University in 2010, in part because the Twins have refused to promote him and in part because he's rarely stayed healthy. He'll turn 24 years old before playing a game above low Single-A and spent back-to-back seasons in Beloit despite hitting .302/.443/.446 there as a 22-year-old the first time around.

That might suggest the Twins don't think much of Roberts' potential, but they gave him a spot in the Arizona Fall League and he hit .446/.565/.662 in 19 games. He led the country in on-base percentage as a college junior and has gotten on base at a .439 clip in the minors, combining patience and strike zone control with an amazing ability to get hit by pitches. Dating back to his final college season Roberts has been plunked 81 times in 235 games.

Along with being an on-base machine Roberts also has 41 steals in 179 games as a pro, but his power has been limited with just 13 homers and he's strictly a corner outfielder defensively. It's tough to get too excited about Roberts' future until he stays healthy and faces more advanced competition, but hopefully the dominant AFL stint convinces the Twins to at least push him aggressively at age 24.

24. Daniel Santana | Shortstop | DOB: 11/90 | Bats: Switch | Sign: Dominican

YEAR     LV      PA      AVG      OBP      SLG     HR    XBH     BB     SO
2010     RK+    144     .264     .285     .421      4     13      3     30
         A-     144     .238     .289     .315      0      7      7     40
2011     A-     409     .247     .298     .373      7     27     25     98
2012     A+     547     .286     .329     .410      8     38     29     77

Daniel Santana all but fell off the prospect map following a 2011 season in which he hit just .247/.298/.373 and moved around the diamond defensively at low Single-A, but the switch-hitter from the Dominican Republic stepped up to high Singe-A last year and showed enough promise to think he can have a big-league future. Santana batted .286 with 38 extra-base hits in 121 games, swiped 17 bases, and struck out in just 14 percent of his plate appearances.

With that said, his overall .286/.329/.410 line wasn't particularly impressive and he drew just 29 walks in 547 plate appearances while being thrown out on 11 of 28 steal attempts. In other words Santana is still pretty rough around the edges and there isn't much in his track record through age 22 to suggest he's capable of being more than a bottom-of-the-order bat. He's hit .266/.313/.398 for his career and hasn't cracked a .750 OPS since rookie-ball in 2008.

Defensively, however, Santana gets positive reviews as both a shortstop and second baseman. He alternated middle infield spots with 2011 first-round pick Levi Michael for much of last season, but Santana eventually emerged as Fort Myers' primary shortstop. If he can remain an asset at shortstop Santana could hit enough to be a decent starter there, but right now he seems to be on the utility infielder track.

23. Zack Jones | Reliever | DOB: 12/90 | Throws: Right | Draft: 2012-4

YEAR     LV      G     GS      ERA        IP       H     HR      SO     BB
2012     RK+     6      0     0.00       6.0       2      0       9      4
         A-     12      0     3.21      14.0       9      1      25      7

Zack Jones had mediocre results in three years at San Jose State, posting a 4.11 ERA in 138 innings spent mostly as a reliever, but his mid-90s fastball and high strikeout rate convinced the Twins to make him their fourth-round pick in June. Jones started eight games in his final college season, but Baseball America's pre-draft scouting report noted that "scouts view him as a reliever" because he lacked a quality third pitch to go with a fastball and slider.

Jones debuted at rookie-level Elizabethon and then moved up to low Single-A Beloit, throwing 20 total innings while working exclusively out of the bullpen. He overpowered hitters, holding them to a .159 batting average and striking out 34 of the 81 batters he faced, but also walked 11. While the Twins are hoping some of the college relievers they drafted in June can become starters, it sounds like Jones and the organization both prefer him in the bullpen.

Even in short outings his control needs a lot of work. He limited walks in his final season at SJSU, but Jones' overall walk rate in college was 4.4 per nine innings and he issued 5.0 walks per nine innings in his admittedly brief pro debut. Still, as a hard-throwing reliever Jones potentially could move very quickly through the minors and has a decent chance to be the Twins' first 2012 draft pick to reach to the majors.

22. Amaurys Minier | Shortstop | DOB: 1/96 | Bats: Switch | Sign: Dominican

As part of MLB's new collective bargaining agreement the Twins were allowed to spend a total of $2.9 million on international prospects last year and they gave $1.4 million of that to 16-year-old Amaurys Minier, a switch-hitting infielder from the Dominican Republic. Ranked by Baseball America as the 12th-best international prospect in last year's signing class, Minier is currently a shortstop but is expected to move to third base once his 6-foot-2 frame fills out.

According to David Rawnsley of Perfect Game he "has immense power from both sides of the plate" but "doesn't have the athleticism" to stick at shortstop. Ben Badler of Baseball America reports that Minier "has drawn attention for his bat speed and plus power from both sides of the plate" with "one of the sweeter swings in the Dominican." However, he added that "scouts have reservations about his ability to hit in games, so his pitch recognition skills will have to improve."

Three years ago the Twins signed Miguel Sano out of the Dominican Republic as a 16-year-old for $3.15 million, but making that type of investment is no longer feasible under the CBA and the $1.4 million they spent on Minier is more than all but three international prospects got in 2012. That doesn't mean he's destined for stardom, but Minier is definitely a high-upside prospect and it's always nice to see the Twins adding a potential impact bat to the system.

21. Michael Tonkin | Reliever | DOB: 11/89 | Throws: Right | Draft: 2008-30

YEAR     LV      G     GS      ERA        IP       H     HR      SO     BB
2010     RK+    10      0     1.08      25.0      18      1      26      4
         A-     13     12     4.29      65.0      76      7      40     18
2011     A-     48      3     3.87      76.2      82      3      69     24
2012     A-     22      0     1.38      39.0      29      1      53      9
         A+     22      0     2.97      30.1      24      2      44     11

Michael Tonkin is a former 30th-round pick for whom "Jason Kubel's brother-in-law" was once his claim to fame, but he's thrived since moving to the bullpen full time in mid-2011 and last year dominated between two levels of Single-A to emerge as someone to watch. Tonkin racked up 90 strikeouts in 69 total innings while holding opponents to a .209 batting average and three homers, posting a 2.09 ERA at age 22.

Plenty of relievers put up great numbers in the low minors every season, but few are 6-foot-7 with mid-90s fastballs like Tonkin. He's moved methodically through the farm system, finally reaching high Single-A midway through his fifth pro season, but that was in part because Tonkin was trying to stick as a starter early on and now that he's in the bullpen to stay there's the potential to rise pretty quickly.

His time as a starter helped develop a three-pitch fastball/slider/changeup repertoire that misses lot of bats and induces a decent number of ground balls. And for a big guy with a big fastball his control isn't bad either, with 20 walks in 69 innings last season and 2.3 walks per nine innings for his career. It's usually silly to get excited about Single-A relievers, but Tonkin's combination of raw stuff, size, and performance since shifting to the bullpen is very encouraging.

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