A Bauer Surge Is Zapping Hitters

The Cincinnati Reds haven’t yet had the breakout season than many — myself included — predicted, but one player who need not shoulder any of the blame for their 8-9 start is Trevor Bauer. His first three outings hint at a repeat of his 2018 All-Star season, and he seems to be on more solid ground than he was back then.

But let’s go back. In one of the more surprising moves of the 2019 trade deadline, the fourth-place Reds (49-56) decided to flip the usual script for teams in their position. The result was a three-way trade with the Padres and Indians that brought Bauer to Cincinnati for Taylor Trammell, Yasiel Puig, and Scott Moss.

The initial returns were…not great. In 10 starts with Cincinnati in 2019, Bauer posted a 6.39 ERA with 12 homers allowed in 56.1 innings. His 4.85 FIP told a more positive tale, but even that mark was well below the team’s expectations. But the Bauer trade was never about 2019. The NL Central didn’t appear to have any juggernauts looming and the potential benefits of having Trammell on the roster were years away; a pitcher like Bauer, meanwhile, could have a meaningful effect on a pennant race now. Bringing in the often-controversial pitcher was always about the 2020 season, and Bauer’s first three starts have been nearly spotless.

Over 19.1 innings, Bauer has struck out a shocking 32 batters against only four walks, good for a 0.93 ERA and a 1.84 FIP. Sure, it’s only three starts, but there are hints of sustainability here that just weren’t present two years ago.

Although shortened by injury, Bauer’s 2018 campaign was easily the best season of his professional career. A 2.21 ERA earned him some Cy Young votes, and he likely would have garnered even more if not for the comeback liner from José Abreu that sent him to the injured list. A 2.44 FIP suggested that his performance was far from just smoke and mirrors, although there was one big concern: his home run rate. Bauer allowed only nine homers in all of 2018, a 6.2% HR/FB rate. A number like that tends to be unsustainable.

Don’t believe me? Let’s look to history. Home runs are one of the three true outcomes, but they have more to do with hitters than with pitchers. From 2002 to 2019, 839 pitchers qualified for the ERA title in consecutive seasons. Of that group, the top 50 pitcher seasons in the first year in terms of HR/FB%, which includes Bauer’s 2018, averaged a 5.6% HR/FB rate. In the seasons immediately following, those 50 pitchers saw their strong HR/FB rates rise to 9.1%, with 47 of the 50 pitchers allowing a higher rate (only Doug Fister improved more than marginally, going from 6.4% to 5.1% between 2010 and 2011). The data shows that flukey low homer rate years are a malady of stars and non-stars alike, from Clayton Kershaw to Mike Pelfrey.

Regression toward the mean for HR/FB% is a generalized rule, but it also specifically applied to Bauer. When we apply ZiPS’ built-in home run estimator to Bauer’s advanced data, it suggests that he should have allowed 21 homers in 2018, 12 more than he actually did. Of the qualifying players with the largest pitcher-friendly zHR discrepancies that year, you have to go down to Max Scherzer at 17th (25.1 zHR vs. 23 actual) to find someone who allowed fewer homers in 2019. (Keep in mind this also accounts for the increase of homers league-wide.)

Twelve additional dingers would have added approximately 24 runs to Bauer’s overall line, enough to bump his 2.21 ERA to 3.44. That’s still a significant improvement, but it is a less dramatic one. His home runs allowed in 2019 increased to 34, and his various contact numbers supported this number, as he had a zHR of 34.6.

Bauer’s initial starts in 2020 have been a different story. Sure, two of them were against Detroit, but the Tigers added some good short-term talent in the offseason and haven’t been nearly as helpless as they were in 2019. This time around, it’s the increase in strikeout rate that is fueling Bauer’s success, as he’s struck out 46.4% of the batters he faced — well ahead of his 30.8% rate from 2018 and his career rate of 25.1%. His four-seamer has been monstrously effective, resulting in only two hits so far while accounting for 19 of his 32 strikeouts. Last year, my colleague Ben Clemens talked about Bauer’s late-season spin increase on the four-seamer. The increase has persisted, with Bauer’s four-seamer having average spin rates of 2,817, 2,836, and 2,741 rpm in his three starts. In his first three outings in 2019, he never cracked the 2,300-rpm mark.

As Ben noted in his piece, there have been whisperings about Bauer’s supposed use of pine tar, something Bauer himself has fueled in his war of words about the Astros increasing Gerrit Cole’s spin rate:

If only there was just a really quick way to increase spin rate. Like what if you could trade for a player knowing that you could bump his spin rate a couple hundred rpm overnight…imagine the steals you could get on the trade market! If only that existed…

— Trevor Bauer (@BauerOutage) May 1, 2018

In any case, I was raised to believe that I only know what I can prove, so it’s not something I’m going to touch on further here.

Bauer’s fastball in 2020 has been elite in terms of vertical drop, losing 3.6 fewer inches than the average, fifth in baseball and firmly in Walker Buehler/nasty reliever territory. Remember, this is a stat that doesn’t rely on opposing offenses being incompetent! Despite his velocity dipping from 94.6 mph to 93.3 mph, the rising fastball illusion has allowed it to punch well above its weight class. After all, you can’t fake stuff. Also, while Bauer’s changeup was never truly a key pitch in his arsenal, he has largely abandoned it so far in 2020. The below pitch usage graph from Baseball Savant outlines how his usage has changed over time:

While 2018 and 2019 didn’t feature meaningfully different approaches, the sea change is apparent in his first starts of 2020. As noted, the changeup has nearly disappeared from his repertoire. He’s clearly been more confident with that fastball and is even less prone to nibbling when behind as a result, directly challenging hitters to hit his hardest stuff. His trend of being less reliant on his breaking pitches with two strikes that started in 2019 has continued this year. Per Brooks Baseball, sliders and curves made up the majority of his two-strike pitches against both lefties and righties in 2018, but the percentage of breaking pitches in those situations dropped into the 40s last year and is now in the high-30s. Bauer’s cutter has more or less replaced the changeup as his go-to change-of-pace pitch against lefties.

One thing to remember about Bauer’s cutter is that it’s more in the breaking ball category than the usual fastball-slider collaboration. He throws his slower than most pitchers do; of the 126 hurlers with 100 innings from 2018-2020 who threw pitches classified as cutters, Bauer’s came in 118th in velocity. In both 2019 and 2020, only Phil Maton’s has had more downward vertical movement. Unsurprisingly, Maton considered his cutter to be a hard breaking pitch.

Bauer’s almost utilizing his like his old change, using it to keep a batter off-kilter but rarely turning to it to punch batters out with two strikes (he’s only thrown five with two strikes, and only one against a righty):

There’s a strong case to be made that the strikeouts are for real. From the early data, ZiPS suggests Bauer deserves a K/9 rate of nearly 15, with a zSO of 31 strikeouts compared to his actual 32. ZiPS was a believer in a Bauer resurgence coming into 2020, projecting him to finish eighth among pitchers in the National League with 1.5 WAR. His hot start has been enough to bump that to fifth (2.1 WAR), the leader in a trio of consecutive Reds, ahead of Sonny Gray and Luis Castillo. The success couldn’t come at a better time financially for Bauer, as he’ll hit free agency for the first time after the 2020 season. Before this year, ZiPS projected that a five-year Bauer extension ought to cost a team $104 million; he’s already moved the needle enough for ZiPS to now say $113 million. Raising your stock $3 million per start? Eat your heart out, Gerrit Cole!

The Reds have fallen 4 1/2 games behind the Chicago Cubs, but in this year’s wacky postseason format, they’re still a lucky coin flip away from the playoffs. Bauer’s early-season performances may help the team “fix” that coin. A big Bauer season may get the Reds into the playoffs and more money into his pockets, while for fans, it may be a noteworthy example of the virtuous effects of a team investing in their roster instead of strip-mining it.