Update on Nolasco and the stretch

Earlier in the week, I put up a Pitch f/x attempt trying to determine whether Ricky Nolasco had a significant problem pitching out of the stretch. I calculated a couple statistics in the article, but I did not have the league averages or the splits for runners on and bases empty. Of course, we couldn’t tell how significant those splits Nolasco showed were without putting them into proper context, so I’ll give it a try here. Friend of the Maniac’s Nick Steiner, aka vivaelpujols (VEP), was gracious enough to lend a hand and toss me the numbers I was looking for. What follows is the league context for those splits.

First off, let’s compare Ricky’s overall numbers versus the league average. These are a bit off because I used a static strikezone while VEP’s data comes from using the dynamic zone for top and bottom limits. Still, I think a comparison is worth noting.

I’ll ignore the ground ball rate against righties, though I suspect it’s around 42-45%. You can see that in this case, Nolasco is pretty significantly better than the league average in most categories. He was better at keeping the ball in the zone and getting hitters to chase and whiff and pitches.

Now, let’s take a look at the splits. VEP provided a weighted average of splits for each of the four categories. The splits were calculated as (bases empty split – runners on split). This method was used to avoid a selection bias (pitchers who allow more runners on are going to be weaker pitchers). Here are your results for Nolasco and the league.

When you look at these comparisons, they seem pretty telling. At least according to last season, Nolasco’s pitch performances out of the stretch fared signficantly worse than his work with the bases empty. According to the data, the league averaged closer splits in each category other than Watch%, the one category Nolasco performed at below league average. Nolasco got significantly more chases out of the zone and more pitches in the zone when in the windup compared to the stretch than the league average did. In fact, the league performed worse at Chase% with bases empty than with runners on, while Nolasco was almost 5% better. Also, remember the sizable split in ground ball rates as well, something that Nolasco already has some trouble with given his natural fly ball tendencies.

I think this sheds some more light and makes the findings more significant. With more seasons under his belt, we may be able to tell whether this is a one-time occurrence or an issue Nolasco may have to deal with. If it is an issue, whether it’s the presence of runners “pressuring” him or a mechanical problem with his stretch delivery, the coaching staff should be made aware.