Bud Norris Figured Out His Platoon Issues

When the Orioles first acquired Bud Norris I wrote that he was actually two different pitchers. When facing right-handed batters he basically only threw a fastball-slider combination, but had a four-pitch mix against left-handed batters.

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Back then I posted this image, that showed Norris’ repertoire against lefties:

This repertoire against lefties never really served Norris well, as he’s never been very good against left-handed batters. Over his career Norris has held righties to a .312 wOBA, which is actually pretty good. This has always been a result of his deadly fastball-slider combo. LEfties though have posted a .350 wOBA against Norris, which has always proved to be his weak point. That different may not seem too significant, but that has worked out to a nearly 1 run difference in FIP over the course of his career (4.66 vs. LHH, 3.63 vs. RHH).

So far in 2014 Norris hasn’t really changed his approach to left-handed hitters. Here is his pitch usage against left-handed hitters in 2014:

There are some minor changes here, his fastball usage is up about 7%, and there are some nominal changes in his sinker and slider usage, but generally it’s pretty close. The results though, have been very different.

In 2014 righties have posted a .324 wOBA against Norris while lefties have posted a .321 figure. Remarkably there’s pretty much no platoon split in there, which makes him much more successful as a starting pitcher.

The main reason? Norris’ change up has become a true weapon for him. From 2012 – 2013, left-handed batters hit .353 with a .508 slugging percentage against Norris’ change. So far in 2014 those numbers have plummeted to a .143 batting average and a .286 slugging percentage. The development of Norris’ change has actually made his slider better too with opponents hitting slightly worse against that pitch than they did over the previous two seasons.

According to pitch values, an effort to measure the value of a specific offering per 100 pitches, Norris’ change up is the 18th best in baseball this season. That’s ahead of guys like Anibal Sanchez, Corey Kluber, and Sonny Gray. From 2012 – 2013, Norris’ change up was the 74th best change (that’s 13th worst) change up in MLB among starters who qualified. Over that time it was worth -2.37 runs per 100 pitches, but in 2014 it has been worth 1.10 runs per 100 pitches. That’s a 3.47 run swing, per 100 pitches. Bud has thrown about 170 changes ups this year, which means that his changeup alone is worth a roughly .3 fWAR improvement over the offering of the past few years (note: this is a very rough calculation to give a sense of scale. His changeup hasn’t actually been worth .3 fWAR).

Let’s compare the two change ups. The first GIF below is from August 5th, 2012 when Norris was still pitching for Houston:

The GIF is a little quick, but you can see that the pitch is pretty straight with little to no fade. It basically serves as a change of speed, but not even a great one because it’s pretty close in velocity to his slider.

Now below we have a change up from exactly two years later on August 5th, 2014. This time Norris is pitching for the O’s and his change up is much improved:

That pitch looks almost like a curve ball, but it’s not. It’s just a very good change up. From 2012-2013 Norris’ change up averaged 4.66 inches less vertical drop than you’d expect from a pitch with no backspin. It did however drop about 5.5 inches more than his fastball. In 2014 it’s dropping about half a foot more, and maintaining a full 6 inches of separation from his fastball.

The pitch is no longer a show-me change, it’s now a true weapon for Norris. The biggest knock on him as a starter was that he couldn’t get lefties out, but that’s pretty clearly no longer the case. Call it a renaissance or whatever you want, but Bud Norris is in the rotation to stay.