With Gerrit Cole, arguably the top pitching prospect in the minors, arriving in the big leagues with a successful debut on Tuesday for the Pittsburgh Pirates (6.2 IP, 2 ER, 7 H, 0 BB, 2 K; 2-run single), the focus turns to the next crop of prospects who could follow suit.
Zack Wheeler is likely to make his major league debut with the Mets as early as next week, while last week's Triple-A mention on this feature, Kyle Gibson, should be in Minnesota by the end of the month.
Here's the latest installment of "which pitching prospect has been the most impressive at his level as of late?" and "which has been the most disappointing?"
RHP Johnny Hellweg, Milwaukee Brewers
Season stats: 3.06 ERA, 70.2 IP, 49 H, 44 BB, 48 K
While the walk-to-strikeout rate doesn't scream "future big leaguer," just about everything else does when it comes to Hellweg. Armed with a mid-90s fastball, the 24-year-old has been keeping the ball on the ground, working deep into games and dominating right-handed hitters.
The 6'9" right-hander has also allowed just three earned runs in 27 innings over his last four starts. While the team contemplated making Hellweg a reliever as early as this season, his success in the Triple-A Nashville rotation has probably put that talk to rest for the near future. Look for him to debut in the Brewers' rotation sometime in the second half.
LHP Sean Gilmartin, Atlanta Braves
Season stats: 5.40 ERA, 66.2 IP, 80 H, 27 BB, 45 K
The 28th pick in the 2011 draft, Gilmartin began his first full pro season in Double-A and reached Triple-A by the end of the season, as the Braves figured he was close to major league ready. As evidenced by his struggles in 2013, he wasn't quite as ready as many had thought.
Projected as a back-of-the-rotation starter in the majors, the 23-year-old lefty doesn't have the velocity on his fastball to succeed when he's not spotting his pitches where he wants them. This has been the case far too often in 2013, and he's gotten hit hard, including his last start on Sunday when he allowed nine earned runs and nine hits in 3.2 innings.
With Alex Wood in the major league bullpen to help make up for the loss of setup men Jonny Venters and Eric O'Flaherty and J.R. Graham out with a shoulder injury, the rotation depth in Atlanta's system isn't nearly as deep as it was when the season started.
RHP Kyle Hendricks, Chicago Cubs
Season stats: 2.14 ERA, 71.1 IP, 61 H, 16 BB, 61 K
Acquired from the Rangers in the July 2012 deadline deal for Ryan Dempster, Hendricks has an impressive career walk-to-strikeout ratio (254.2 IP, 40 BB, 222 K) on his resume that is reminiscent of two other former Rangers prospects who were traded during the previous deadline, Robbie Erlin and Joe Wieland.
Whenever a pitcher who has had success in the lower minors without overpowering stuff advances to Double-A and Triple-A, it's always interesting to see if he can continue dominating. The 23-year-old Hendricks, who had a 2.99 ERA in High-A last year with 18 walks and 123 strikeouts in 147.2 innings, has been up to the task so far at Double-A.
Over his last eight starts, he's pitched shutout ball every other time out, and he's completed at least seven innings in four of those eight starts. At this pace, he could reach Triple-A later in the season and possibly even see the majors if the Cubs trade more than one big league starter by the deadline.
RHP Matt Barnes, Boston Red Sox
Season stats: 5.87 ERA, 53.2 IP, 62 H, 16 BB, 64 K
Barnes completely dominated in five Low-A starts (26.2 IP, ER, 12 H, 4 BB, 42 K) to begin his pro career in 2012 and also held his own (3.58 ERA, 93 IP, 85 H, 25 BB, 91 K) after a quick promotion to the High-A Carolina League. And just as he seemed to have a handle on Double-A hitters, he's taking his lumps over his last two starts.
The 19th overall pick in the 2011 draft, Barnes has allowed 11 earned runs over his last 5.2 innings to raise his ERA near 6.00. Still, he's probably the best pitching prospect in the organization despite his rotation mates, including Drake Britton (3.25 ERA) and Anthony Ranaudo (2.43 ERA), enjoying much more success in 2013.
RHP Daniel Winkler, Colorado Rockies
Season stats: 2.35 ERA, 76.2 IP, 46 H, 20 BB, 90 K
Someone forgot to tell the 23-year-old that pitching in the High-A California League is supposed to be way more difficult than the Low-A Southern Atlantic (Sally) League.
After posting a 4.46 ERA and a .269 opponents' batting average in 25 starts last season, Winkler has dominated at the next level and particularly as of late. Over his last three starts, the former 20th round pick out of the University of Central Florida has allowed just three earned runs and eight hits in 19.2 innings with three walks and 24 strikeouts.
RHP Kyle Zimmer, Kansas City Royals
Season stats: 6/32 ERA, 52.2 IP, 53 H, 23 BB, 67 K
Taken just one pick (fifth overall) after Orioles pitcher Kevin Gausman in the 2012 draft, Zimmer is struggling to get hitters out just as Gausman is. The only problem is that Gausman, who is eight months older, is at the big league level, while the 21-year-old Zimmer is getting beat up in High-A ball.
Zimmer's overall numbers are fine, but he's getting killed with runners on base (.329 opponents' batting average), which has resulted in the 6'3" right-hander allowing five earned runs in four of his last five starts.
RHP Robert Stephenson, Cincinnati Reds
Season stats: 2.97 ERA, 66.2 IP, 52 H, 17 BB, 85 K
Stephenson isn't likely to rise to the majors as quickly as Tony Cingrani did in 2012 when he went from High-A to the majors in a matter of months. But the 20-year-old, who profiles as a future top-of-the-rotation starter with an explosive mid- to upper-90s fastball, is the prize arm in the Reds farm system.
In his last six starts, Stephenson has allowed just four earned runs and 19 hits in 38 innings pitched with six walks and 50 strikeouts. That is complete dominance of a level, and it wouldn't be surprising if he's in High-A before long.
RHP Hudson Boyd, Minnesota Twins
Season stats: 6.02 ERA, 55.1 IP, 58 H, 27 BB, 43 K
Taken in the first round (55th overall) of the 2011 draft, Boyd had success in 13 starts (2.95 ERA) with short-season Elizabethton in the Appalachian League in 2012. With nearly identical peripherals in 2013, however, Boyd's ERA has more than doubled in this first taste of full-season ball.
The 20-year-old has allowed 23 earned runs and 32 hits over his last 26.1 innings pitched, including six homers. He had only allowed one homer over his first six starts combined.