Digging into Chase Anderson’s struggles with the long ball

Prior to the start of the 2018 season, the prevailing belief was that in order for the Milwaukee Brewers to be competitive once again, Chase Anderson would need to continue his breakout performance. While it would be a lot to ask of any pitcher to repeat a 2.74 ERA, it was assumed that another strong season from Chase would be necessary to lead a rotation with Jimmy Nelson lost to injury and no “ace” acquired via trade or free agency.

As it turns out, the Brewers have been competitive and are right in the thick of both the Divisional and Wild Card races with a little over a month left in the regular season. Fortunately, they’ve been able to get to this point without receiving top-of-the-rotation production from Anderson. After his most recent start on Sunday when he allowed four runs across 5.0 innings, Chase’s earned run average rose to 4.04 through 140.1 innings, making him right around the league-average in terms of run prevention.

Anderson’s peripheral numbers are cause for even greater concern. He’s been in the zone less often this season and has seen his walk rate spike from 2.61 BB/9 to 3.21 BB/9. He’s not missing bats near as frequently, losing a point off his swinging-strike rate (down to 9.1%) and more than a batter-per-nine off his strikeout rate, which now sits at 7.25 K/9. His rate of hard contact allowed has risen some five points (to 36.4%). In the eyes of run prevention estimators like FIP- (128) and DRA- (120), Anderson’s overall performance this year is seen as well below-average.

The most obvious concern about Chase’s work on the mound has been his propensity to give up the long ball. Anderson had issues with the home run earlier in his career (1.3 HR/9 from 2014-16) but during his 2017 campaign, he allowed only 14 baseballs to fly over the fence in 141.1 innings. So far this season, in one fewer inning, Anderson has served up twice as many dingers - 28 in total, more than any other pitcher in the National League. His rate of 1.80 HR/9 also ranks last among qualified NL hurlers. So what’s different?

On the whole, his pitch selection is generally similar to last season. He’s selecting his three offspeed pitches - changeup, curveball, and cutter - at roughly the same rate as he did in 2017, give or take a couple percentage points. His curve and cambio both still grade out as plus pitches, at least in terms of their linear weights from Fangraphs. Anderson is throwing his sinking fastball about eight percent less often this season, favoring his four-seam fastball a bit more than he did last season. But his overall four-seam usage lines up with his career totals. His spin rate is down a little bit in 2018 but not concerning so (-33 RPM). He is using his fastball in a similar manner to last season, as well, typically keeping the ball to his glove side and up in the strike zone:

Batters hit only .227 against Chase’s four-seamer in 2017 and he allowed only six home runs with the pitch. This season, hitters have managed a mere .205 average against Anderson’s heater, but have posted a .298 ISO and pounded 16 of them over the fence. Chase’s wFB (weighted fastball runs above average) in 2017 was +7.4 runs. So far in 2018, his wFB is -1.1 runs. Only a dozen qualified NL starters have been less effective with their fastballs this season.

If you’ve watched Chase pitch this year, it probably doesn’t come as a surprise as to what the culprit for his diminished success seems to be. Here is a chart featuring his average fastball velocity throughout his career. Notice any outliers?

After a velocity spike in 2017, Anderson’s fastball has come back down to Earth this season. He averaged 93.1 MPH last season and was topping out at 97 at times, but Chase is down to a 92.4 MPH average in 2018. He’s been very inconsistent with the heat from start to start; it seems like some days he comes out firing right away and sits in the 93-94 MPH range, while in other games he struggles to get much beyond the 90-91 MPH velocity band.

Anderson has lost the extra zip on his fastball but hasn’t changed the way he’s been using it, giving him much less margin for error up in the strike zone. Because he doesn’t have the same ability to reach back and blow the fastball by hitters consistently like he did last year, it has caused Anderson a lot of neck-straining while he turns to watch his fastballs get pounded over the fence.

From the start of his career with Arizona through his first season with Milwaukee in 2016, Chase Anderson was a fly-ball heavy pitcher who struggled with home runs but still produced solid results (4.26 ERA in 418.2 IP) while fitting into the back-end of the starting rotation. Things changed in 2017, when Anderson added some fastball velocity and prevented runs like an ace. But now that the extra zip on his fastball is gone, he has regressed back to the pitcher that he was during his first three seasons in the big leagues. League-average is still certainly a useful pitcher, to be sure, but it’s not the Chase Anderson that Milwaukee was hoping for when they signed him to a modest extension last winter.

Statistics courtesy of Fangraphs