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Also in this series: 1-5, 6-10, 11-15, 16-20, 21-25, 26-30, 36-40.

35. Scott Diamond | Starter | DOB: 7/86 | Throws: Left | Trade: Braves

YEAR     LV      G     GS      ERA        IP       H     HR      SO     BB
2009     AA     23     23     3.50     131.0     152      5     111     53
2010     AA     17     17     3.52     102.1     113      4      90     39
         AAA    10     10     3.36      56.1      53      2      33     15
2011     AAA    23     23     5.56     123.0     158     11      90     36
         MLB     7      7     5.08      39.0      51      3      19     17

Scott Diamond was a worthwhile pickup when the Twins plucked him from the Braves' system in last winter's Rule 5 draft, but rather than simply keep him in the majors as a long reliever they traded former second-round pick Billy Bullock to Atlanta for the right to stash him in the minors. Not only was Bullock the better, higher-upside prospect, making the swap lopsided in talent alone, the Twins ended up promoting Diamond to the majors in July anyway.

Once there he struggled in seven starts with a 5.08 ERA, 19-to-17 strikeout-to-walk ratio, and .317 opponents' batting average in 39 innings, showing the mediocre raw stuff that limits his long-term potential. His average fastball clocked in at just 88.9 miles per hour and batters also did damage against his 83-mph changeup. Seven bad starts aren't necessarily meaningful and Diamond did a good job inducing ground balls, but the marginal stuff matched his track record.

He's allowed just 13 home runs in 33 career starts at Triple-A, but that comes with a 4.87 ERA and 123-to-51 strikeout-to-walk ratio in 179 innings from a left-hander who'll turn 26 years old this summer. For the first time in a long time the Twins' system is short on starting pitching and Diamond is nice to have around as depth, but he seems unlikely to be more than a fifth starter and giving up Bullock to keep him when the Twins basically already had him was a mistake.

34. Jairo Perez | Third Base | DOB: 6/88 | Bats: Right | Sign: Venezuela

YEAR     LV      PA      AVG      OBP      SLG     HR    XBH     BB     SO
2009     RK-    142     .217     .324     .317      1      9     17     12
2011     A-     316     .337     .413     .580     15     36     32     48

Jairo Perez signed with the Twins out of Venezuela as an 18-year-old in 2006 and hit .338 over 48 games in the Dominican summer league in 2008. That earned him a 2009 promotion to the rookie-level Gulf Coast League, but he hit just .217 in 37 games and then missed all of 2010 following Tommy John elbow surgery. Perez was totally off the prospect radar, but the Twins moved him up to low Single-A last year and he responded with a monster half-season.

He hit .337/.413/.580 with 15 homers and 20 doubles in 74 games, showing decent strike-zone control with 32 walks versus 48 strikeouts in 316 plate appearances. Perez also committed 17 errors in just 49 games at third base and likely lacks the range to play second base despite seeing some time there for Beloit, but the Twins can obviously find a home for him further down the defensive spectrum if he keeps hitting.

Everything about Perez was surprising last season, but his power was particularly noteworthy from a guy listed at 5-foot-10 and 160 pounds. Because of the season lost to elbow surgery Perez is already 24 years old and he may prove to be a one-year wonder, but posting the second-best OPS in the entire Midwest League is worth noticing in a farm system severely lacking in impressive production above rookie-ball last season.

33. James Beresford | Shortstop | DOB: 1/89 | Bats: Left | Sign: Australia

YEAR     LV      PA      AVG      OBP      SLG     HR    XBH     BB     SO
2009     A-     505     .289     .342     .313      0     11     34     70
2010     A-     540     .297     .349     .363      1     25     34     56
2011     A+     545     .270     .328     .299      0     13     43     63

James Beresford showed some power development while repeating low Single-A in 2010, doubling his extra-base hit total and adding 50 points to his slugging percentage, but the skinny shortstop from Australia moved up to high Single-A last season and took several steps backward. He failed to homer in 545 plate appearances and managed just 12 doubles, producing a measly .299 slugging percentage despite a solid .270 batting average.

To put that lack of power in some context, consider that no hitter in Twins history with 500 plate appearances in a season has ever posted an Isolated Power below .040. He had a .029 Isolated Power for Fort Myers and a .037 Isolated Power for his career. Beresford has a good enough glove that he certainly doesn't need to be a slugger, but at some point he'll have to show some ability to drive the ball or it's tough to see him developing beyond a utility man.

Beresford is 6-foot-2 and an above-average athlete, but for whatever reason he's been unable to put on muscle since the Twins signed him as a 16-year-old. He's still just 23 years old, so that could change, and he's done a nice job controlling the strike while drawing a fair number of walks for someone to whom pitchers will gladly throw strikes. With even a little pop he'd be very intriguing and as always the Twins could use some long-term middle infield help.

32. Terry Doyle | Starter | DOB: 11/85 | Throws: Right | Rule 5: White Sox

YEAR     LV      G     GS      ERA        IP       H     HR      SO     BB
2009     RK+    12     10     2.98      57.1      51      1      75     15
2010     A-      7      7     0.96      47.0      31      2      58     12
         A+     20     20     3.71     121.1     115     13      99     34
2011     A+     11     11     2.84      73.0      71      3      49     11
         AA     15     15     3.24     100.0      91      8      73     22

With the No. 2 pick in the Rule 5 draft the Twins selected right-hander Terry Doyle from the White Sox. Doyle's strong performance in the Arizona Fall League got the Twins' attention, but that involved just eight starts and he split the regular season between Single-A and Double-A despite being a 25-year-old drafted out of college in 2007. He fits the Twins' mold with good control and a low-90s fastball, throwing 173 innings with a 3.07 ERA and 122/33 K/BB ratio.

Rule 5 picks must remain in the majors all season or be offered back to their original team, but last year the Twins got around that by overpaying the Braves to retain Diamond as a minor leaguer. That move never made sense to me and made even less sense when Diamond was in Minnesota around midseason anyway, so presumably by passing on higher-upside arms to take Doyle with the No. 2 pick they're willing to simply keep him in the majors as a long man.

Vice president of player personnel Mike Radcliff told John Manuel of Baseball America that the Twins think Doyle "has got the ability to be a fourth or fifth starter" with velocity that ranges from "marginal" to "average." Not exactly the upside you'd ideally like to target atop the Rule 5 draft and his declining strikeout rate isn't encouraging from a 26-year-old with 15 career starts above Single-A and none at Triple-A, but Doyle isn't without potential.

31. Tyler Grimes | Shortstop | DOB: 7/90 | Bats: Right | Draft: 2011-5

YEAR     LV      PA      AVG      OBP      SLG     HR    XBH     BB     SO
2011     A-     159     .225     .316     .406      4     13     13     53

As part of their uncharacteristically loading up on college middle infielders last year the Twins drafted Wichita State shortstop Tyler Grimes in the fifth round and signed him for a $132,500 bonus. He showed minimal power as a junior, but hit .300 with 57 walks in 65 games for an excellent .467 on-base percentage. He also struck out 61 times in 65 games and Baseball America's pre-draft scouting report noted both his lack of consistency and all-or-nothing swing.

Those concerns proved accurate in his professional debut, as Grimes skipped rookie-ball and hit just .225 with 53 strikeouts in 42 games at low Single-A. He also failed to maintain the standout plate discipline that he showed in college, drawing just 13 walks in 159 plate appearances, but did flash more pop than expected with four homers and 13 total extra-base hits for a solid .181 Isolated Power.

Grimes' future at shortstop is in question because he made a ton of errors in college, continued to do so during his pro debut, and the Twins used him at second base about one-fourth of the time in Beloit. His arm strength isn't in question, but Baseball America noted that "he plays out of control at times." In theory at least Grimes' speed and on-base skills make him a welcome addition to a Twins system that's perpetually lacking middle infield depth.