Minor League Barometer: Finally Time for TB's Jennings?

The minor-league exodus continues for the next wave of phenoms, as Anthony Rizzo of the Padres and Mike Moustakas of the Royals got the call from their respective ballclubs. Meanwhile, teams replenished their farm systems during last week's MLB draft, and a first-round pick (Corey Spangenberg, No. 10 overall by San Diego) has even signed. While there do not appear to be any Bryce Harpers, Stephen Strasburgs or Ken Griffey Jr.s in this year's crop, we'll soon found out whether prospects like Gerrit Cole, Anthony Rendon, Trevor Bauer and others have to what it takes to become stars.

Let's look at the rest of the minor-league scene in this week's Barometer.

UPGRADES

1. Desmond Jennings, OF, TB - It seems like the Rays have brought up everybody but Jennings over the first two months of the season: Sam Fuld, Brandon Guyer, Justin Ruggiano, to name a few. However, it's clear Tampa Bay is just biding its time until the team is truly ready to call upon their stud prospect and hand him the reins. Jennings is making a case for right now, hitting .372/.476/.558 over his last 10 contests for Triple-A Durham, with one home run, five RBI and three steals. For the season, the 24-year-old outfielder is hitting .290/.384/.483 with nine home runs, 29 RBI and 12 steals through 61 games. With Matt Joyce dinged up and Sam Fuld's average dipping below .230, Jennings' promotion could be coming shortly.

2. Collin Cowgill, OF, AZ - Paul Goldschmidt gets the pub due to his massive power, but Cowgill has been just as productive for the Diamondbacks. His last 10 games have been ridiculous: the 25-year-old outfielder is batting .512/.543/.837 with two home runs, nine RBI and three steals for Triple-A Reno over that span. His season line is almost as impressive, as Cowgill is hitting .369/.434/.607 with 11 home runs, 41 RBI and 19 steals through 61 games. Cowgill has really cured his ills against right-handed pitching; after batting .269/.338/.460 against righties in 2010, Cowgill has made an amazing turnaround this season, hitting .378/.436/.589 against righties. The D-Backs have hinted that both he and Paul Goldschmidt could be called up by the end of July.

3. Chih-Hsein Chang, OF, BOS - Chang is having a breakout season for the Red Sox, and the 23-year-old appears to have finally found his power stroke. After swatting a career-high 11 home runs in 2010, he already has 10 dingers with 36 RBI through 45 games this season for Double-A Portland. He's been hot of late as well; over his last 10 contests, Chang is batting .415/.442/.927 with four home runs and 12 RBI. Overall, he is batting .315/.356/.642. Although Chang still does not draw enough walks, he also does not strike out an inordinate amount. If his power continues to develop and his plate discipline improves, he could be a sleeper prospect for the BoSox.

4. Nathan Eovaldi, P, LAD - An 11th-round pick in the 2008 draft, the 21-year-old Eovaldi has burst onto the prospect map this season. He underwent Tommy John surgery in 2007, which scared off some teams at draft time. However, he still can hit 95 mph on the radar gun. Eovaldi has a 2.83 ERA and 65:22 K:BB ratio through 57.1 innings for Double-A Chattanooga. Both improved control as well as the ability to miss bats has spurred on this breakout campaign for Eovaldi; opposing hitters have a .217 BAA, and his K:BB ratio has improved for the third straight season. At 6-foot-3, 195, the righty has a nice frame as well. He still needs to work on pitching out of the stretch, as he has a 7.06 ERA with runners on base. However, he has been able to limit the damage overall and is a prospect to watch.

5. Deck McGuire, P, TOR - McGuire isn't talked about nearly as much as fellow classmates and 2010 draftees Drew Pomeranz and Matthew Harvey. However, he has been dealing for High-A Dunedin nevertheless. The 21-year-old righty has a 3.07 ERA and 70:29 K:BB ratio through 70.1 innings for the Jays. Over his last two starts, McGuire has fanned 18 batters while walking just four, allowing three earned runs in total. Although his inability to keep the ball down at the higher levels could come back to haunt him, for now opposing batters are hitting just .221 against the 6-6, 220-pounder. With Kyle Drabek in the majors and Zach Stewart struggling, McGuire is arguably the top pitching prospect in the Toronto organization.

6. Jose Altuve, 2B, HOU - Altuve's scorching start with High-A Lancaster earned him a promotion to Double-A, and the 21-year-old has not let up. In 12 games for Double-A Corpus Christi, Altuve is batting .408/.431/.735 with two home runs, 12 RBI and two steals. With 15 home runs and 42 steals in 2010, Altuve has an intriguing combination of power and speed, particularly from a middle-infield position. Although he doesn't draw many walks, it is hard to argue with his results thus far. His stat line before the call-up to Double-A is pretty impressive: .408/.451/.606 through 52 games with High-A Lancaster, popping five home runs, driving in 34 runs and swiping 19 bags. He's extremely small at 5-7, 170, but size won't matter if he continues to play at this torrid pace.

Honorable Mention

1. Devin Mesoraco, C, CIN
2. Pat Corbin, P, AZ
3. Dellin Betances, P, NYY
4. Ryan Verdugo, P, SF
5. Brad Peacock, P, WAS

DOWNGRADES

1. Leonys Martin, OF, TEX - Martin landed on the disabled list with a slight herniated disc in his back. Back injuries are fickle, and often difficult to assess and overcome. Martin was having a standout start to his season before the injury too, batting .357/.444/.583 with three home runs, 18 RBI and eight stolen bases through 22 games with Double-A Frisco. The 23-year-old Cuban defector does not project for much power, and one has to wonder whether the back injury will not only diminish it even further, but also affect his ability to swipe bases. Although he has excellent speed, Martin was already thrown out seven times in 15 chances before the injury. Track Martin's recovery closely.

2. Brad Holt, P, NYM - After a promising start that finally looked like Holt was coming around, he has regressed once again. His last start for Double-A Binghamton was abysmal, as the 24-year-old allowed seven runs in just 3.0 innings. Although he gave up just four hits, Holt walked six batters in the contest. Sadly, that wasn't even his season high; on May 19, the 6-4, 194, right-hander walked an astonishing eight batters. It has clearly been all about control, or lack thereof, for Holt. Opposing batters are hitting an anemic .206 against him, but he has tallied more walks (40) than strikeouts (38) on the year. After an awful 8.34 ERA last season, the No. 33 overall selection in the 2008 draft may be running out of time to prove he can be even a serviceable big-leaguer.

3. Hector Gomez, SS, COL - Although Gomez is on pace for career-high power numbers, he's had considerable difficulty managing the strike zone this season for Double-A Tulsa. The 23-year-old is batting just .205/.242/.381 through 50 games with the Drillers. He has drawn just 10 walks over that span, while fanning 53 times. Since hitting .316 in 2006, Gomez has never hit above .275/.310/.423 at any level. His seven home runs and 27 RBI are decent, particularly for a shortstop, but his inability to make contact will continue to leave questions about his ability to hit for average at the major-league level.

4. Drake Britton, P, BOS - The Red Sox have developed some serious pitching talent over the past few seasons (Jon Lester, Clay Buchholz, Daniel Bard), and Britton is supposed to be next in line. He had a 2.97 ERA and 78:23 K:BB ratio in 75.2 innings last season in Low-A. However, 2011 has been vastly different for the 22-year-old lefty. Britton has a bloated 7.42 ERA and 33:31 K:BB ratio through 47.1 innings for High-A Salem. After surrendering just five home runs all last season, Britton has already yielded seven this year. His wildness has been his main bugaboo, as opposing batters are hitting exactly the same against him this year (.240) as they were last year. Time is on his side, but clearly this season hasn't gone exactly as planned for one of the better prospects in the Red Sox system.

5. Michael Burgess, OF, CHC - Burgess still has plus-power, but his average has tumbled this season for High-A Daytona. The 22-year-old is batting .193/.300/.382 through 58 games for the Cubs. On a positive note, Burgess does have nine home runs and 38 RBI, and has also drawn 32 walks. However, no power numbers are good enough to justify a .193 batting average, and he has also been punched out 62 times in 2011. The 49th overall selection in the 2011 draft has not hit above .265 since 2007, and has struck out at least 116 times in each of the last three seasons. It is questionable if Burgess will ever hit for average at the higher levels.

6. Michael Olt, 3B, TEX - Another Texas-sized injury for the Rangers, as Olt broke his left collarbone, requiring surgery. He will miss 10-12 weeks, which could mean his first "full" season in the minors is all but over. The 22-year-old out of UConn had emerged as a stellar phenom as well, hitting .286/.395/.508 with 10 home runs and 34 RBI through 54 games prior to the injury. Although he should make a full recovery, his progression to the majors will obviously be stunted a bit until he can regain health and his previous form. Once he comes back, he'll need to work on his strikeouts; Olt was punched out 51 times in 54 games while at High-A Myrtle Beach.

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