Minor League Barometer: Rocks' Wheeler Speeding Along

The Astros will get a look this week at how top prospect Jordan Lyles fares against the pinnacle of competition, as Lyles makes his major-league debut against the Cubs. The 20-year-old righty tore through the minors in less than three seasons after being drafted at 17 years old with the No. 38 pick in the 2008 draft. In 59.0 innings this season with Triple-A Oklahoma City, Lyles posted a 3.20 ERA and 41:16 K:BB ratio. Lyles has been hot lately too, which helped spur his promotion: the 20-year-old has allowed two runs or fewer in six of his last seven starts. The 'Stros certainly hope the crown jewel of their system will quickly pay dividends at the big-league level despite his youth.

As far as the rest of the prospect map, let's look at this week's Minor League Barometer.

UPGRADES

1. Tim Wheeler, OF, COL - The Rockies outfield is certainly crowded, but that doesn't take away from Wheeler's stellar start to the 2011 season at Double-A Tulsa. The 23-year-old is batting .330/.412/.644 with 14 home runs, 45 RBI and nine steals through 48 games for the Drillers. Over his last 10 contests, Wheeler has been even better, hitting .357 with a .449 OBP. Wheeler is penciled in for a likely 2012 debut, and Dexter Fowler and Eric Young Jr. don't exactly have a stronghold on the center-field position. The 2009 first-round draft pick has certainly become a hot commodity this season.

2. Matt Moore, P, TB - Moore has fanned at least seven batters in each of his last six contests for Double-A Montgomery. His last start on Thursday might have been his best of the young season, as the 21-year-old southpaw tossed six scoreless innings against Jacksonville. Moore walked just one batter while punching out 11 for the game. Opposing batters are hitting an anemic .198 against him this season. With a 2.91 ERA and 76:14 K:BB ratio to boot, Moore remains one of the best prospects in baseball.

3. Tyler Skaggs, P, AZ - A product of the Dan Haren trade, Skaggs has allowed no more than one run in four of his last six starts for High-A Visalia. The 19-year-old also had his best start of the season last Thursday, allowing one run on four hits in 7.0 innings for the Rawhide. Skaggs issued just one free pass, while striking out 10 batters. On the year, Skaggs has a 3.27 ERA and 81:24 K:BB ratio. He gets a bevy of ground balls as witnessed by his 1.73 GO:AO ratio. With opposing hitters posting a mere .215 BAA, Skaggs is emerging as an elite prospect for the Diamondbacks.

4. Jarred Cosart, P, PHI - Cosart battled elbow problems in 2010, but appears healthy in 2011 and has been lights out lately. In his last 20.2 innings for High-A Clearwater, Cosart has allowed just one earned run. Over that span, the 21-year-old righty has yielded just six hits and six walks while fanning 20. Although he's been a bit wild, Cosart possesses an impressive 2.15 GO:AO ratio for the season, and opponents are hitting .213 against him. Already the best pitching prospect on the Phils' farm, Cosart is making a push to regain his status as an upper-echelon phenom.

5. Jacob Turner, P, DET - Turner has quietly gone about his business in 2011, amassing 52 strikeouts compared with 14 walks in 60.1 innings for Triple-A Erie. At 20 years old, he is among the youngest players in Triple-A but has not been overmatched. A .217 BAA and 2.69 ERA is proof of that. With Andy Oliver, Rick Porcello and Brad Penny not exactly mowing down the competition, Turner could see the Detroit rotation before summer is through.

6. Liam Hendriks, P, MIN - Kyle Gibson gets the pub, but Hendriks has been just as effective for the Twins. The 22-year-old from Australia has posted a 3.12 ERA and 51:13 K:BB ratio through 52.0 innings for Double-A New Britain. Opposing batters are hitting just .228 against the right-hander. Largely a ground ball pitcher, Hendriks has outstanding command, having never walked more than 16 batters in a season up to this point in his minor-league career. If he can continue to pound the strike zone, as most Twins pitchers are taught, as well as stay off the DL, he could become a special hurler for Minnesota.

Honorable Mention

1. D.J. LeMahieu, 2B, CHC
2. Juan Nicasio, P, COL
3. Zach McAllister, P, CLE
4. James Darnell, 3B, SD
5. Alex Cobb, P, TB

DOWNGRADES

1. Kirk Nieuwenhuis, OF, NYM - Nieuwenhuis hurt his shoulder making a diving catch last week, landing him on the disabled list. He was batting .302/.407/.521 with six home runs, 14 RBI and five steals through 47 games for Triple-A Buffalo. The Mets have also gotten back some of their players from the DL recently, including Angel Pagan and Jason Bay. With Carlos Beltran playing well and still in New York for now, Nieuwenhuis may not have a place to play even if he comes back at full strength. But hey, at least he hasn't been bad-mouthed by the Mets owner yet, right?

2. Mark Rogers, P, MIL - The No. 5 overall pick in the 2004 draft out of high school, Rogers is now 25 and spending his second stint on the disabled list this season due to lingering carpal tunnel syndrome. Rogers has been injury-prone throughout his minor-league career, including offseason shoulder surgery last winter. At one time, Rogers was slated to be a possible fill-in for Zack Greinke to begin the 2011 season. However, his inability to stay healthy forced the Brew Crew to demote him to the minors instead. The clock is ticking on Rogers to prove he can actually stay on the field and be a productive major leaguer.

3. Tyler Matzek, P, COL - Not to beat a dead horse, but Matzek has been simply awful in 2011 for High-A Modesto. The No. 11 pick in the 2009 draft, Matzek has a horrific 9.82 ERA and 46:37 K:BB ratio through 33.0 innings for the Nuts. It appears as though not even Matzek knows where the ball is going at times. He lasted just one inning in his last start Friday, walking five batters en route to five earned runs. With such high expectations coming out of the draft, Matzek clearly has a ton of work to do on his mechanics to turn around his young career.

4. Wade Miley, P, AZ - After a career-year in 2010, Miley has come crashing down in 2011. This season, the 24-year-old has a bloated 7.30 ERA and 27:15 K:BB ratio through 40.2 innings for Double-A Mobile. The 6-foot-1, 220, lefty is allowing opposing batters to hit .310 against him. Miley remains wild as well; even during his breakout campaign in 2010, he walked 65 batters while fanning 113 in 153.0 innings between two levels. Miley does not project as much more than an innings-eater, back-of-the-rotation type of hurler, and he may even have trouble getting to that level at the bigs if he continues to allow so many baserunners.

5. Jaff Decker, OF, SD - A minor downgrade for Decker, who is batting just .135 with no home runs and 14 strikeouts over his last 10 games for Double-A San Antonio. Although his eye remains outstanding (41 walks in 48 games), Decker has fanned 57 times over that span and is hitting just .235 on the season. With numbers like that, the 21-year-old reminiscent more and more of a left-handed version of Nick Swisher. Likewise, be aware that Decker has never had a fully healthy season since coming onto the scene in 2008.

6. Ross Detwiler, P, WAS - It's been tough sledding for the No. 6 overall pick from the 2007 draft, as the 24-year-old Detwiler has posted a 5.80 ERA and 38:20 K:BB ratio through 54.1 innings for Triple-A Syracuse. Opposing batters are hitting an absurd .336 against the left-hander, who spent time in the majors in 2007, 2009 and 2010. Did the Nats push Detwiler too fast, too soon? Although that issue cannot be corrected now, Detwiler has fizzled with the big club and remains a fringe prospect at this time, after getting a $2.15 million signing bonus in 2007.

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