One of the biggest surprises in the 2012 season was David Phelps. In 57.1 innings started and 42.1 innings of relief, the right-hander pitched to a 3.34 ERA with a 23.2 K% and 9.2 BB%. Phelps fared better in relief appearances, where he held batters to a .209/.281/.359 slash and a 2.76 ERA. As successful as he was in relief, he still pitched to a 3.77 ERA in games started, and he might earn the chance to start in 2013.
Throughout the minor leagues, Phelps showed off his command and the ability to pitch to contact, but what changed in 2012 was his strikeout rates. His 23.2 K% in 2012 was his highest seasonal total while playing professionally. When entering the 2012 season, most of the scouting reports said that none of Phelp's strike out pitches stood out, but the results from his 99.2 major league innings speak differently.
His curveball was responsible for a whiff rate over 16%, while the MLB average whiff rate on curveballs is slightly under 12%. The rest of his out pitches were useful in different situation, as the slider/cutter maintained about a 13% whiff rate against right handed pitchers, and the changeup was responsible for a 7% whiff rate against lefties and drew a 55% groundball rate.
In 2012, David Phelps' pitches outperformed the expectations. Whatever changes he made at the beginning of season added movement, and believe it or not, it would be a difficult task to find an unsuccessful pitcher with the amount of overall movement on his four-seam and sinker. Though he doesn't possess the velocity or deadly changuep, both the vertical and horizontal movement on his fastballs mimic that of Justin Verlander. That's not to draw comparisons between pitchers, but to instead show just how rare Phelps' four-seam and sinker are.
As we go forward, Phelps will likely continue to be successful with his fastballs, drawing the right combination of groundballs and flyballs. Whether his strikeouts will continue is harder to determine. Because the success of his strike out pitches are limited to batter-handedness, hitters will see less variation, and there's more of a chance that theyse hitters could catch on to his pitch usage or overall game plan.
Even if Phelps continues the type of strikeout success he had in 2012, the biggest warning sign of regression come from his FIP. His 3.34 ERA was only that low because of an extremely high 82.5% left on base rate. His 4.32 FIP is nearly 1 whole run higher than his ERA, and this is a better predictor of Phelp's future than his small 99.2 inning sample size.
He is still 26 years old, and with the type of improvement he showed in 2012, there's now hope for him to become a mid-rotation starter. If he gets the chance to be the 5th starter in 2013, he's probably looking at a performance closer to his 2012 FIP. Although it's regression, Phelps still has upside.