Medlen was one of the breakout stars of 2012 but didn't join the Braves rotation until July 31.
While it's way too late to buy low on a player that's already broken out in the first half of the season —Diamondbacks starting pitcher Pat Corbin and Brewers shortstop Jean Segura would be the best examples—plenty more could break out between now and the end of the season.
If you're looking for this season's version of Chris Carter, who had just 17 first-half at-bats in 2012 before hitting 13 homers and knocking in 34 runs after the All-Star break for the Oakland A's, or Kris Medlen, who didn't join the Braves rotation until July 31 and then might've been the best pitcher in baseball the rest of the way (9-0, 0.97 ERA, 83.2 IP, 57 H, 10 BB, 84 K in 12 starts), consider these eight breakout candidates.
Houston hasn't shied away from promoting pitching prospects (Jose Cisnero, Paul Clemens, Brett Oberholtzer) early in the season, but they've chosen to break them into the majors in relief roles. They'll likely forgo that route, however, for their best pitching prospect, Jarred Cosart, who has a 2.49 ERA in 43.1 innings (20 BB, 47 K, .197 opponent's batting average) with Triple-A Oklahoma City.
The 22-year-old, who many scouts project to pitch out of the bullpen, has allowed just one homer on the season and throws in the mid-'90s. In a rebuilding season, the Astros will be able to give him a long look to determine if he can stick in a starter's role.
If you thought d'Arnaud's broken foot combined with John Buck's blistering start (.905 OPS in first 24 games) crushed all of d'Arnaud's fantasy value for 2013, you probably should've been reminded of a few things. Fractured bones heal, typically with a recovery rate of six to eight weeks—d'Arnaud is expected back in late June, about six weeks after his injury—and Buck just isn't that good.
Just take a look at the 32-year-old Buck's career numbers. Regression was coming sooner or later. Since hitting his 10th homer of the season on May 3, Buck is 6-for-44 with no homers and 18 strikeouts.
Once d'Arnaud returns, expect him to play regularly for a few weeks in Triple-A and he could then be in New York by late July. If Buck happens to get hot again, the Mets could have a nice trade chip. If not, then it's time to see what their top prospect d'Arnaud can do in the majors. Either way, the 24-year-old should play a lot.
Despite the struggles of their injury-plagued starting rotation, the O's have resisted the temptation to bring up Gausman, who might be the most talented pitcher in their organization.
While the 22-year-old, who was the No. 4 overall pick in the 2012 draft, gets his feet wet in Double-A, Baltimore has given a total of 12 starts to Jake Arrieta, Zach Britton, Freddy Garcia, Steve Johnson, Jair Jurrjens and Josh Stinson. Only Garcia has recorded a quality start (6 IP or more, 3 ER or less). He has two in his four starts.
In the meantime, Gausman has a 3.11 ERA with five walks and 49 strikeouts in 46.1 innings over eight starts. The O's don't want to rush the kid, but losing six straight games to fall five games behind the first-place Yankees in the AL East has to have them considering an earlier-than-expected promotion for Gausman.
With an opening in their rotation that needs to be filled on Friday, the Twins are bypassing top pitching prospect Gibson for journeyman Samuel Deduno. It's understandable that this frustrates Twins fans. They've seen plenty of Deduno and it probably wasn't much fun watching. In his 15 starts for the Twins last season, he walked 53 batters while striking out 57 in 79 innings.
Still, the 29-year-old Deduno is just a temporarily fill-in for Gibson, who the organization wants to see more consistency from before calling him up for good. The 25-year-old, who missed most of last season recovering from Tommy John surgery, has tossed 24.2 scoreless innings total in three of his last five starts, including two shutouts. The problem is that the two starts in between weren't very good (7.2 IP, 9 ER, 18 H).
He's getting closer, though, and should be in Minnesota within a month. It also wouldn't surprise me if he was its best starting pitcher by the second half of the season.
The Twins have been patient with their rookie center fielder, despite his terrible start at the plate (.495 OPS). While the 23-year-old should be in Triple-A right now, he's learning on the job in the big leagues and has only shown flashes of why he's been a top prospect for years.
Although he's currently marred in a 2-for-20 slump, he's shown some improvement over the last month —.246 BA (14-for-57) with three homers, three doubles, a triple and six walks between April 21 and May 13. He's not quite there yet, but he's talented enough to figure it out eventually, very likely after a having a few months under his belt and a few days off during the All-Star break to regroup.
The Rangers could've pursued another outfielder this past winter, and Michael Bourn certainly would've been a nice fit as the team's starting center fielder and leadoff man. But they stuck with Martin, a high-profile signee out of Cuba back in May 2011, and the move is starting to pay off.
The 25-year-old started slow with just five singles in his first 26 at-bats, but he's hit .333 (22-for-66) since with two homers, two doubles, three triples and five stolen bases.
At the time of his signing, Martin was considered a close to major league ready center fielder. Although it's taken a bit longer than expected, he appears to be coming into his own now. The pressure from signing a five-year, $15.5 million big league contract is also being shed as he continues to answer questions about his ability with his on-field performance.
Like most 22-year-old rookies, Rosenthal experienced his ups and downs early on. They didn't last long, though. After blowing leads in two of his first four appearances of 2013, Rosenthal has recorded 13 holds —tied for second in baseball—and hasn't allowed a run in his last 9.2 innings. He has six walks and 32 strikeouts in 22.1 innings pitched.
While Edward Mujica is doing a terrific job as the team's closer, his stuff doesn't compare to Rosenthal, who could be next in line for the job. Mujica is 13-for-13 in save opportunities, however, and seems to have a pretty firm grasp on the gig.
Mujica won't go the full season without blowing a few saves, though. If they happen to come in a bunch, expect the team to give the closer's job to Rosenthal, who is unlikely to relinquish the role for the remainder of the season.
If you've been paying close enough attention, Smoak should at least be on your radar by now. While he's not making noise with many homers—he had one in his first 38 games—the-26 year-old is quietly having a big month for the Mariners with a .934 OPS, including homers in two of his past three games.
While the homers are down—he hit 19 in 2012—his .366 on-base percentage is well above his career rate coming into the season (.306) and a good sign that he's starting to feel more comfortable at the plate. If this is the case, expect the homers to become more frequent as they've done the past few games.