Skills Growth Drives Wily Peralta Breakout

Heading into his second full season, Wily Peralta got some sleeper love and it was easy to see why. A high octane fastball that averaged 94.8 mph last year, ranking fourth in velocity among qualified starters, will always get fantasy owners excited. And although his 2013 strikeout rate was an uninspiring 16.1%, he posted much better marks throughout his minor league career, suggesting potential for upside if he could translate his stuff into results. For those who looked past the inflated ERA and below average control and imagined what could be, you were duly rewarded with a 3.53 ERA and 17 wins.

On the surface, Peralta is exactly the type of pitcher I love to bet on a breakout. He induces grounders at a high clip, has the big fastball and minor league history to provide optimism that more strikeouts are on the way, and his control is acceptable enough. Since walk rates typically decline through ages 25 to 26 before leveling off and then rising again, you want that to be the wart, if there is one at all. Hoping for an improvement in control is much better than hoping for more strikeouts or grounders.

And sure enough, Peralta did take that step forward with his control in his age 25 season. Although it’s not obvious given that his F-Strike% actually dropped a tick, his overall rate of strikes thrown did increase, albeit not significantly. It was a meaningful amount though and resulted in a walk rate that was suddenly on the good side of the league average line. Unfortunately, without another jump in strike percentage, it appears that his walk rate improvement is largely unsustainable. Based on my xBB% formula, his walk rate should have been 8.4%, but it’s a level that still does represent an improvement over 2012, and his 8.9% xBB% mark that year. He has never shown very good control in the minors, so we’ll have to rely on blind optimism here that a young pitcher suddenly gets it and starts throwing more strikes.

Peralta’s fastball velocity jumped a full mile per hour, averaging nearly 96 mph, ranking third in baseball this year. But it didn’t help either his four-seamer or two-seamer to generate any additional swings and misses versus 2013. His two-seamer though has remained truly excellent, generating an above average SwStk%, along with gobs of grounders. In fact, it has induced a higher rate of swinging strikes than the four-seamer, along with significantly more grounders. So why then does he continue to throw his four-seamer more often? Perhaps a change in mix would help him out and might be something listen to if we hear rumblings of such during the spring.

His slider has generated a slightly below average SwStk%, but because it also induces lots of grounders, it is actually quite a good pitch. After the slider is the rarely used changeup, which makes Peralta essentially a two-pitch pitcher. And with just the fastball and slider, we start worrying about platoon issues. In 2013, he endured those from a skills perspective, displaying worse control and an inability to induce grounders against lefties. But his wOBA against wasn’t as significantly worse against lefties than righties as you would expect given the xFIP splits. So basically he benefited from greater fortune against left-handed batters, leading to results that were worse, but not as bad as they should have been.

The tide turned in 2014 though, as exactly the opposite happened. His skills against lefties improved dramatically, as he sharpened his control and actually posted an xFIP against lefties that was slightly better than against righties. But a .345 BABIP and 15.1% HR/FB rate did him in, resulting in a .361 wOBA against by lefties. He posted a lower ball rate on all pitch types against lefties in 2014 and generated a higher whiff rate on his changeup and four-seamer. The improvement of his changeup must prove to be real for Peralta to continue to have success against batters of either handedness.

With the seeds of something real good, Peralta will continue to intrigue. A switch to more two-seamers/sinkers at the expense of his four-seamer could provide the upside to boost both his strikeout and ground ball rates even further. But the key probably lies in his control and growth of his changeup. Count me in for the under on Steamer’s 4.24 ERA projection.