by Matt Wilkes

What’s up with Trevor Bauer?

When the Reds traded for Trevor Bauer and teamed him up with pitching coach Derek Johnson in late July, they hoped to get the 2018 version of the right-hander. Bauer has shown how dominant he can be in two of his starts in a new uniform, striking out 11 in seven innings on Aug. 9 and 19.

His other starts have ranged from bad to disastrous. Bauer has an 8.23 ERA, 5.27 FIP, 4.80 xFIP, and 4.38 SIERA in 35 innings as a Red. The ERA estimators are nearly half his actual ERA, showing his performance in terms of what he can control hasn’t been as bad. But those are all below-average numbers, too, and certainly not what the team expected when they dealt their top prospect and Yasiel Puig for Bauer.

Bauer’s strikeout and walk rates are in line with his career marks. He’s in the midst of his third straight season with a strikeout rate above 26%. His control, however, has regressed. Bauer has a 9.4% walk rate (9.2% with the Reds), up from 8.0% in each of the previous two seasons. The league average for starting pitchers is 7.7%. Contact quality hasn’t changed either: 88.4 mph exit velocity and 38.6% hard-contact rate with the Indians, 88.3 and 35.0% with the Reds.

Luck hasn’t exactly been on his side. It would be easy to chalk up his rough start as a Red to his .379 batting average on balls in play — it’s unsustainable, and the ball will start to bounce his way. Tough luck also rears its ugly head in his expected statistics.

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These stats show what Bauer’s batting average, slugging percentage, and wOBA should be based on average exit velocity and launch angle. Since those numbers haven’t changed much, the expected stats during his time with the Reds roughly line up with his season numbers. But the actual results show a huge disparity. To put this into context, 119 starting pitchers have faced at least 100 batters since Aug. 1, and not a single one has a larger difference between actual wOBA and expected wOBA than Bauer. (Side note: Sonny Gray has benefited in the opposite way. Only one pitcher — Jeff Samardzija — has a larger negative differential between wOBA and xwOBA, which shows he’s had some luck involved in his recent run of dominance.)

Based on these metrics, Bauer isn’t performing much worse than he did with the Indians, with whom he posted a 3.79 ERA, 4.15 FIP, 4.29 xFIP, and 4.18 SIERA. Luck doesn’t explain everything, though. His FIP and xFIP with the Reds are worse because he’s giving up more home runs and getting fewer ground balls. That being said, this has been a season-long issue — not one that suddenly popped up when he came to Cincinnati.

The four-seam fastball is the main culprit behind his homer problem. Four of the seven long balls allowed with the Reds and 16 of 30 on the season have come on four-seamers. Many of the home runs Bauer has allowed with the pitch have come in predictable fastball counts. He’s allowed five on the first pitch, four in 3-2 counts, and four more in 3-1, 1-0, and 2-0 counts. Interestingly, Bauer is throwing fewer four-seamers in all of those counts — minus 3-2 — while upping his cutter usage. (Bauer has thrown more fastballs when ahead in the count this season.)

He’s made himself less predictable, but the results haven’t shown that. He hasn’t lost any velocity (94.5 mph), and he’s added spin (83rd percentile). Those are two crucial components of an effective fastball and what made Bauer effective last year. Although batters still hit his four-seamer hard when they connected (88.3 mph EV, .377 xwOBA on contact), keeping it high in the zone helped him limit home runs (4).

Whether by design or unintentionally, Bauer isn’t getting his four-seamer up in the zone quite as well this season. Take a look at the heat maps (2018 on the left, 2019 on the right):

While this probably doesn’t fully explain his fastball’s ineffectiveness, it’s a contributing factor. The juiced baseball plays a role in the equation, too. Nine pitchers have already allowed at least 30 home runs this season, and that number could easily climb into the twenties by season’s end. For reference, here’s how many pitchers allowed 30-plus homers the last five seasons:

  • 2018: 7
  • 2017: 17 (Note: Another year with a supposedly juiced baseball)
  • 2016: 13
  • 2015: 5
  • 2014: 0

Bauer isn’t going to give up two homers per nine innings moving forward like he has with the Reds. But the sky-high rate represents an area of concern. The home runs were almost certain to come up from 2018, when he allowed only 0.46 per nine innings and maintained a 6.2% HR/FB. Remember, pitchers will almost always regress toward the league average in HR/FB. He’s at 1.41 HR/9 and 15.1% HR/FB this year, right at the league averages for starting pitchers.

The alarming part here is that his ground-ball rate has fallen off a cliff.

Perhaps this is a result of a focus on throwing high in the zone. Bauer’s slider and changeup — which accounted for nearly 30% of his grounders last year — have both regressed.

Additionally, Bauer has seen overall regression with his slider, changeup, cutter all season. FanGraphs’ Alex Chamberlain outlined the decreased performance of his cutter and slider a few weeks ago. In part due to a loss in velocity, Bauer is getting fewer swings and misses and has a higher xwOBA on both pitches. It’s not surprising that both have gone downhill simultaneously. A cutter and a slider have similar movement and grips. The main difference is velocity, with the cutter (84.5 mph) being thrown harder than the slider (79.5).

The cutter has lost some vertical and horizontal movement compared to last year, which further explains some of its problems. But the slider is getting more drop and ride. Only six pitchers, including Sonny Gray, get more horizontal movement versus the league average with the pitch.

That increase hasn’t led to better results in part because hitters have just stopped swinging at the pitch as often. The same goes for his cutter.

Bauer regularly starts his slider and cutter on the plate so that they finish outside the strike zone and batters miss. Hitters aren’t taking the bait this year. Take a look at the Swing% profile on his slider as an example (2018 on the left, 2019 on the right):

Of course, this also means hitters are having an easier time identifying the pitches, which only fuels the notion that Bauer is tipping pitches.

The changeup has seen the largest dip in performance, although it has made less of an overall dent in his production since he throws it only 5% of the time.

Just like the cutter, Bauer has lost some movement and nearly 1 mph with his changeup. He’s been attempting to replicate Luis Castillo’s elite changeup since coming to the Reds, although he hasn’t unveiled it much in game action yet.

Similar to most pitchers when they struggle, Bauer is clearly dealing with multitude of issues in his disappointing 2019 season. The pitch tipping speculation doesn’t seem too far-fetched when you consider he throws six different ones. Throwing each pitch the same way without giving any indication of what’s coming is challenging enough for someone with two or three offerings.

Bauer is one of the most cerebral pitchers in the game — or at least one of the most outspoken ones about his analytical approach — and has similarly minded coaches Derek Johnson and Caleb Cotham. The Reds clearly have their eyes set toward winning in 2020, and Bauer returning to form would make an enormous impact in reaching those lofty aspirations.

Matt Wilkes got hooked on Reds baseball after attending his first game in Cinergy Field at 6 years old, and he hasn’t looked back. As a kid, he was often found imitating his favorite players — Ken Griffey Jr., Adam Dunn, Sean Casey, and Austin Kearns — in the backyard. When he finally went inside, he was leading the Reds to 162-0 seasons in MVP Baseball 2005 or keeping stats for whatever game was on TV. He started writing about baseball in 2014 and has become fascinated by analytics and all the new data in the game. Matt is also a graduate of The Ohio State University and currently lives in Columbus. Follow him on Twitter at @_MattWilkes.