What Happened To Brian Matusz?

Here's what’s crazy about the Brian Matusz situation: he was good last year. Legitimately good. Just last year! Against 206 batters, split nearly evenly between righties and lefties, he had a solid 71 ERA-, 85 FIP-, and 98 xFIP-. His K-BB rate was an excellent 17.5%, nearly 30% better than a league-average reliever.

But he couldn’t find it again in 2016. Against 35 batters he put up an ERA- of 290, FIP-, of 303, and xFIP- of 248. That’s while striking out a paltry 2.9% (just one batter!) and walking an astounding 20%. On top of that, he surrendered three HR in six innings, with two coming in the same game.

It's just six innings, but -- what the hell happened?

Matusz stopped throwing strikes. Hitters waited him out, taking their walks, and crushed what he gave them, refusing to strike out. The speed with which hitters caught up to him, and the severity with which they tagged him, is odd to me. Matusz was never stellar but he was never this bad.

His Zone% plummeted:

Hitters didn't chase like they did in 2015. In particular, they spat on his fastball and slider, which he'd used as strikeout pitches:

In 2015, these two pitches accounted for 50 strikeouts and 12 walks of 206 batters, amounting to a 24.2% K rate and 5.8% walk rate.

In 2016, these pitches accounted for one strikeout and seven walks of 35 batters, for terrible 2.8% strikeout and 20% walk rates.

When they did get a pitch to their liking, batters didn’t miss. Opponents' Z-Contact% jumped from 67.2% to 75.8%.

Hitters connected with his fastball and change-up more often:

When they connected, they did more damage:

These weren't fluke hits. Exit velocity shows Matusz's fastball, and to some extent his change-up, were very hittable:

Whew. That's a pretty ugly story. The speed and magnitude of hitters' adjustment to Matusz astounds me. Was it bad luck? Poor sequencing? It wasn't velocity; his fastball was down about 0.80 MPH, which isn't good, but that drop isn't enough to explain the graphs above. And his other pitches were flat or even up. His horizontal release points separated out a bit compared to last year, but again, could those fractions of an inch really make that much of a difference?

The first graph tells the story to me: Matusz lost his command. He couldn't locate his fastball like he used to in order to put hitters away. That, and perhaps some pitch-tipping (or amazing advance scouting) led to hitters laying off the heater and the slider because they were ahead in the count. Thus the high walk rate and increased damage on pitches in the zone.

Finally, his HR/FB rate of 30% indicates some bad luck. Matusz had been keeping the ball on the ground better than ever before; his GB/FB rate of 1.10 was the highest of his career. That's what you want to see from a pitcher who's not striking out a lot of batters.

He'll be back in the majors. Matusz is left-handed, 29 years old, and making reasonable money. He's one season removed from a good year and his struggles came on so rapidly and sharply that other teams may see them as a fluke. Besides, his stinker of a 2016 is only six innings.

Plus, he's coming from the Orioles. Some team is bound to look at him and think they can do what the Cubs did to Jake Arrieta. Neither the Orioles nor the Braves need him, but there are 28 more teams who might.

Fare thee well, Brian Matusz. You never lived up to your promise as the number four overall pick, but you were a good reliever for a few years and you deserve a tip of the cap from this fanbase.