Charlie Morton is a breakout candidate for the Pirates

The Pittsburgh Pirates’ sterling starting rotation certainly has its share of variety.

At the top, we find A.J. Burnett and Francisco Liriano, two veterans of the American League who complement their mid-90s fastballs with a true swing-and-miss off-speed pitch. For Burnett, it’s his spiking knuckle-curve, while Liriano wields a swerving slider that has never been better.

However they get it done, Burnett and Liriano give the Pirates what they need as they participate in their first real pennant chase in over a decade. Two times out of five, Pittsburgh has an MLB-tenured guy on the mound competing at (or near) his full potential.

Jul 12, 2013; Pittsburgh, PA, USA; Pittsburgh Pirates starting pitcher Charlie Morton (50) throws a pitch against the New York Mets during the first inning at PNC Park. Mandatory Credit: Charles LeClaire-USA TODAY Sports

At the other end of the experience spectrum, we have 25-year-old Jeff Locke and 22-year-old Gerrit Cole. Both are getting their first real opportunities to pitch in a major-league rotation, and both are holding up well to the strain. While Locke has shown some batted-ball luck regression and Cole could face innings restrictions as the year goes along, the Pirates are a better team for having them.

Finally, in the middle of the Pittsburgh five lies Charlie Morton. At 29, the New Jersey native is the same age as Liriano, but injuries and inconsistent performance have limited him to 97 starts in six MLS seasons. In 2011, the 6-foot-5 righthander remodeled his delivery in the mold of sinkerballer Roy Halladay and had his best full year to date, posting a 3.83 ERA in 29 starts.

Morton was off to a decent beginning last season, but right arm discomfort shut him down and led to Tommy John surgery after just nine starts. He returned to the big leagues this June, compiling a 4.07 ERA in 48 2/3 innings leading into Wednesday night’s start – his 10th of 2013 – against Miami at PNC Park.

Looking beyond the superficial stats, Morton’s strikeout-to-walk ratio is a career-high 3.17, nearly a full strikeout better than his previous best rate. Moreover, as often happens after elbow repair, his four-seam fastball velocity is up, humming consistently in the mid-90s. Morton still leans on his two-seamer to induce ground balls and quick outs, but he appears to be working with superior stuff after his recovery.

All of this means Morton’s mediocre results this season are very likely to improve. His strikeouts are up (7.0 per nine innings), his walks are down (2.2) and his hits allowed (10.0) are consistent with his career norms. Fewer baserunners and balls in play tilts the odds in Morton’s favor, more than is expected from a ground-ball specialist.

If Locke continues to drop off, the Pirates will need someone else in the rotation to pick it up. Although Wandy Rodriguez is on target for a September return from elbow concerns, Morton is the most likely Bucco starter to take a leap forward in the coming weeks.