April 20, 2012:

“If you ask me, ‘Who’s the best pitcher in the world?’” I say, ‘Me.’

Entering his third full season, Ivan Nova is fighting for a rotation spot that he is confident he will keep. The reason for the uncertainty is his disappointing 2012 season, in which he threw 170.1 innings with a 5.02 ERA. This came on the heals of a magnificent 2011 campaign where he threw 165.1 innings with a 3.70 ERA.

What caused Super Nova to turn into Ivan the Terrible in 2012? His batted ball data tells us two things:

1) His ground ball rates dipped while his fly ball rates increased
2) His HR/FB rate absolutely skyrocketed

Here are his 2011 numbers compared to his 2012 numbers:

GB%: 52.7% / 45.2%
FB%: 28.9% / 32.4%
HR/FB%: 8.4% / 16.6%

The HR/FB rate is especially ugly – it was the 7th worst of all MLB pitchers who threw 100 or more innings last season. What caused this to happen?

We know it wasn’t a velocity issue, because Nova’s harder pitches (his fastball and his slider) did not see a drop off:

Average fastball, 2011: 92.4 mph
Average fastball, 2012: 92.8 mph
Average slider, 2011: 86.5 mph
Average slider, 2012: 87.2 mph

And we know that his stuff wasn’t anymore “hittable” on average, because his contact rates were solid:

2011 Contact%: 84.8%
2012 Contact%: 79.5%
2011 Z-Contact% (contact inside strike zone): 93.6%
2012 Z-Contact%: 90.3%

If anything, Nova’s stuff was slightly LESS hittable in 2012. It seems pretty clear that Nova’s pitches didn’t lose much quality from year to year.

So, why the bloated ERA? There is a school of thought that would say that it was largely due to luck. To some extent, that is true – Nova was at least a little unlucky last year. HR/FB rates, for instance, tend to have a large amount of variance from year to year. It’s highly unlikely that Nova will be at 16.6% again. He should be much closer to a standard rate (right around 11%) in 2013.

And then there’s his fastball. The pitch yielded twice as many HR in 2011 as it did in 2012, and saw its GB rate plummet from 52.5% in 2011 to 43.9% in 2012. He wasn’t throwing it any softer in 2012, and according to his heat maps, he wasn’t locating it any worse (courtesy of FanGraphs):

Ivan Nova NoMaas Yankees Heat Map

Ivan Nova NoMaas Yankees Heat Map

Since there wasn’t a significant change in velocity or command, it seems like there was some element of random luck involved here. Granted, it is possible that 2012 is closer to Nova’s “true talent” level and he simply got extremely lucky in 2011. We really can’t say for sure just yet. However, it seems likely that, in regards to the fastball, his “true talent” level is somewhere between these two seasons.

The slider, however, is a different story. The pitch generated an impressive 39.22 whiff per swing rate, but opponents managed a .263/.282/.439 line off of it. While opposing batters were struggling to make contact with Nova’s slider, the ball was jumping off the bat when they did actually connect.

These heat maps for the slider seem to offer a possible explanation for this:

nova_slider_2012 copy

Nova seems to have located the pitch pretty well overall, but he did leave some up in the zone – and hitters LOVE sliders that hang up in the zone. Batters were likely teeing off when the slider hung, but were whiffing when he threw the pitch well. This is usually an issue of mechanics, especially release point. And remember: Nova is still learning how to throw the slider effectively, and facing quality hitters in the AL East isn’t making the job any easier. If the pitch is going to be effective, though, he needs to keep his mechanics under control.