What Went Right: Ivan Nova’s strikeouts

For all intents and purposes, Ivan Nova’s 2012 season was just short of a total disaster. Instead of taking a step forward and solidifying his spot in team’s long-term plans, he took a step back and became one of the Yankees’ biggest question marks. It’s not all bad though, he did improve his underlying performance and quite substantially as well.

Coming up through the minors, Nova never struck out more than 19.3% (7.14 K/9) of the batters he faced in a single full season. Last year, in his first full big league season, he struck out 13.9% (5.33 K/9) of batters faced. This year that jumped up to 20.5% (8.08 K/9), the 11th highest strikeout rate among qualified AL starters. He held that rate pretty steady during his brutal second half, which is oddly a good sign…

Nova’s increase in strikeouts is due to increased usage of his slider, which is something we first saw in the second half of last year. After throwing the pitch just 3.7% of the time a year ago, he upped that to 12.1% this season while scaling back the usage of his curveball and changeup. Opponents missed on nearly 40% of their swings against the pitch (39.2%, to be exact), which is far above average. That’s pretty darn close to CC Sabathia’s slider (42.8%), just for perspective. Overall, Nova generated a swing and a miss on 9.0% of his pitches this year, up from 6.6% last year.

The strikeout rate improvement was substantial this year, and normally that would result in improved performance. For Nova, it resulted in declining performance. Tough to explain and I really don’t know how, but this isn’t a “he stinks when he strikes guys out so he should stop striking guys out” thing. His walk rate (7.5 BB% and 2.96 BB/9) was rock solid and he still got an above average amount of ground balls (45.2%), so the peripheral stats improved from 2011 to 2012. The problem was that whenever Nova wasn’t striking guys out or getting ground balls, he was giving up homers and extra-base hits. This season was a disaster for Ivan, but the increased strikeout rate (while other core stats remained steady) was certainly a nice silver lining.