Trevor Bauers’ last bad day

On July 16th, Trevor Bauer laid the greatest of eggs. Without even escaping the first inning, Bauer let up four runs on three hits, facing eight batters before he was yanked. It was wihtout at doubt the nadir of his 2017 season, and one of the worst appearances of his career, both in brevity and damage done. It inflated his ERA to its season peak of 5.59, and gave a lot of fodder for those who still don't see everything Bauer could be, even if he isn't there yet. Since then though, Bauer has been one of the best pitchers in the American League. This is the man who was drafted third overall, coming into fruition.

Since that hideous start, Bauer's ERA is a scant 2.69 and he's struck out 26.3 percent of batters while walking only 7.6 percent, as opposed to 9.1 prior to his Oakland start. He’s been this good despite a higher than usual .337 BABIP and a 15.4 percent home run per fly ball ratio, nearly two points above league average. Despite being unlucky, Bauer has dominated. It would be a little silly to think that suddenly he changed everything after one start, but tehre have been decided shifts since July. For instance, and if Brooks Baseball is to be believed, , but he has thrown more sliders since July:

More on that in a bit though. Something should be made of his phasing out the sinker, or two-seamer if you like. There was a piece in May on Fangraphs, and then another in September, about the death of the sinker as a viable pitch. The sinker is used to get ground balls, but in a battle of flyball hitter and groundball-inducing pitch, who wins? Truly a question for the age. It was going out of vogue already, but Bauer needed more dimension in his pitching, something aside from the four-seam and the curve to lean on, and take advantage of a sterling defense. Unfortunately, everyone hits fly balls now, no matter how you try. The A’s didn’t kill his two-seamers really, but that was almost a death knell for them that day.

When that article by Jeff Sullivan form this September published, Kyle Boddy of Driveline Baseball noted how disappointing the death of the sinker/two-seam was because he and Bauer had worked hard on it last winter. WIth the ever-expanding bottom of the strike zone the last several years, it stands to reason you'd want to throw the ball down there more, and the sinker/two-seamer is the best at it. The natural growth from a dropping zone would be an uptick in better low ball hitters, as the A's have piled up. All this to say, Bauer focused on the wrong thing, and seems to have phased it out. He learned, he just unfortunately had to spend a winter on the wrong skill. Whether or not that had anything to do with the A’s start is a question for the biographers.

Now, that slider. Bauer has been throwing it more and more according to that graph, though I am suspicious of that. Depending on the site, the pitch that moves in the mid to high 80s that runs toward lefties is alternately classified as a cutter or a slider. He’s definitely been throwing something that moves like that, but I don’t think it’s two separate pitches. It’s more like akin to the “slutter” that Jake Arrietta made famous a year or two ago. It’s still a biting pitch that runs away from righties, but it dances between classifications. Like a poor man’s version of Corey Kluber’s “breaking pitch”. In conjunction wiht Bauer’s love of the high fastball and his crippling curve, this third pitch (and the occasional change-up) gives him a dimension that truly baffles the batter. Accordng to TexasLeaguers.com, his cutter usage jumped five points to 15.7 percent after the 16th, and the slider showed up on the Statcast tracking from out of nowhere. That alone feels like it proves the point. Bauer found the dimension he was missing.

Baseball doesn’t do anything in a linear fashion. It comes in fits and starts. But that day in Oakland was the last real terrible outing for Bauer. There were other three or four run outings, but those went into the sixth or seventh innings. That’s just a disappointing day, not truly ugly. With the bullpen he has, four runs in the modern run environment is enough to give the team a chance at least. Whether by happenstance or because he had a come to Jesus moment after only being able to get two batters on one of the worst teams in the league out, it’s hard to say. Luck might have had something to do with it, just like the rest of the first half of his season. But this Bauer we’ve seen since August is what’s been expected. Maybe he’ll make that next leap some day, and become Kluber-esque, that consistent domination. But a sub-3 ERA over three months of work (that leaves room for him to still get better) is a terrifying prospect for the third or fourth best pitcher in a rotation. Watching a pitcher flourish and mature like this, it’s one of the best things about baseball.