On Justin Topa, and a weird small sample

Justin Topa has an ERA of 27.00 so far this year, he's also barely thrown a bad pitch. In this article I'll take a look at some conflicting interpretations of the 43 pitches he has thrown for the Brewers in 2021.

The Milwaukee reliever had an excellent debut in the majors last year, with a 2.35 ERA & 1.07 xFIP in 7.2 innings, striking out 12 and walking none. Batted balls against his pitches had a negative average launch angle of -2.2°. This year has been less rosy. A spring training injury side-lined him for most of the season, and in his return he has given up 5 earned runs in just 1.2 IP, striking out none, before being sent down to AAA on 08/15. 

 The reasons for his 2020 success are clear, he throws a power sinker with a ton of movement that he can control, complementing it with a sweeping slider which didn't allow a hit. This pitch mix is a recipe for success, the sinker generating groundballs and weak contact, then with two strikes the slider can efficiently put hitters away. So where did it all go wrong?

The Inning from Hell

Topa's first major league outing of 2021 was relatively uneventful; a scoreless frame in a blowout against the Cubs, with no strikeouts, no walks, no hits. In his next appearance he came into a 2-run game against the Pirates. Jacob Stallings ground out, one up, one down. Then the hit parade started with this hard-hit line drive to center.

  This wasn't necessarily a bad pitch, shaded towards the outer edge of the plate with tremendous stuff, yet Topa was punished for it. Then came a hard grounder straight past the shortstop and successive hits on balls chopped into the ground, scoring three runs in total.

 

 

There was still more to come and Hoy Park found a hole in the shifted defense while hitting a pitch well outside the zone.

Topa got his second (and final) out on an RBI groundout from Ke'Bryan Hayes which could easily have been a double play. After this he was removed from the game.

This inning put the game far out of reach for Milwaukee and inspired some derision from Brewers fans watching. The exit velocities (courtesy of Baseball Savant) of all those hits don't look pretty.

Clearly giving up 5 runs and only getting two outs isn't ideal, but does that actually mean Justin Topa was bad on this occasion?

Maybe, he was actually pretty good?

Don August, former Brewers pitcher, had a high opinion of Topa, he really liked him based on his pitch quality and this leads to a different way to analyse him: don't look at the outcomes. xxxFIP is a statistic which I created to try to estimate ERA from pitch quality alone. It takes the movement, and location of pitches, along with the counts they are thrown in, in order to make predictions of strikeout, walk and flyball rate which are then converted to the ERA scale in an xFIP-like formula. Through the ten batters which Justin Topa faced this season, he's posted the best xxxFIP of any pitcher.

   

 10 batters faced is a ludicrously small sample for any statistic, but that's good company to be in. 

I can also create expected run values from Justin Topa's pitches with no reference to the outcomes as detailed here, this is another statistic where Justin Topa has excelled this season (lower is better). It is bizarre how some of the "best" pitches can lead to awful results, but that's the nature of the game, especially when only looking at a couple of innings. Topa got no strikeouts but he threw plenty of pitches which could have generated them. He reached a two-strike count against his final three batters faced in Pittsburgh, but the hitters managed to foul off excellent pitches such as this one.

Conclusions

So what does all this say about Justin Topa? A glance at his ERA would suggest that he's unplayable, analysis of his pitches by a former pitcher and advanced statistical models say that he's really good. The reality is clearly somewhere in between, Topa will not maintain a double digit ERA in a significant sample, he's also not better than Jacob deGrom.

Pitchers have little control over their batted ball luck and the sequencing of hits against them. This gives me confidence that Topa can come back and pitch well, in line with his 2020 results. The high exit velocities against him are worrying but he should get more strikeouts and allow fewer balls in play if he comes back to the major league team.

 His short time in the majors this year was certainly weirder than most, but I'm confident that he'll be back to play an important part in the Brewers' bullpen in the future.