Trevor Bauer heaved a bunch of curveballs

For just a bit more than five innings on Saturday night, Cleveland Indians pitcher Trevor Bauer was excellent. Through five and a third he had allowed four hits, a run, struck out six and seemed to be firmly in command. Everything collapsed very quickly after he recorded the first out in the sixth, but that's not important here. Right in the midst of the rising chaos, Bauer had a really interesting at-bat against Jake Lamb.

Bauer mixed his pitches pretty well on Saturday night. Of the 102 he threw, 26 were four-seam fastballs, 28 sinkers, 23 curveballs, 21 cutters and four splitters. He faced Lamb to open the second inning, striking out the Arizona third baseman on six pitches. Bauer got him with a collection of fastball variants — two four-seamers, three sinkers and a cutter. He attacked Lamb with similar stuff in the fourth, a trio of fastballs of various types and two splitters. Then in the sixth Bauer went way off script, and gave Lamb a real curveball. Or rather, five of them. Let's look.

Hard to see, since that dastardly Paul Goldschmidt chose to swipe third base as this was happening, but Bauer kind of got away with one here. The ball was up in the zone, and Lamb was plainly letting Goldschmidt go on that one. Goldy doesn’t have a green light to steal when he wants and the D-Backs were still hunting for runs. So Bauer lucked out with Lamb not swinging. That could have gone poorly.

Now that’s a curveball. After seeing one in the first pitch, plainly Lamb wasn’t expecting it again and he bit hard. A classic descriptor of a curve is “knee buckling”. This here is the best example of that.

Nearly the same location. Good take as well as a good pitch from Bauer’s side. It worked once, so why not? In Lamb’s case, he can’t have been looking curve at that point, he’d just seen two in a row, and he likely expected something out of the zone on 0-2 anyway. Plus you have to consider the fact Bauer was nearing 100 pitches in only the sixth. The book is that he walks people so a take here is a good idea, whether it’s the bender or a high fastball.

That’s a dangerous spot for a curveball, especially for a guy who hit 29 home runs last year. Typically the curve should look like it’s belt high at best before it falls off the table. The higher it is, the less of a margin for error you have. But Lamb missed it, so no harm.

Still, an interesting choice for Bauer and Perez.

And he finishes Lamb off with another buried curve. Three of these five pitches were filthy, and they did the job they were supposed to. It was just a strange set of choices. At least, in a conventional sense.

Just for static reference, here’s the pitch mapping of the at-bat.

One aspect of pitching that is still hard to chart is sequencing. It's that part of the batter-pitcher face-off that is the most mental where the pitcher gets to outwit the hitter, at least hopefully. In this case, it’s hard to understand how a pitcher can just throw the same thing over and over. Mariano Rivera got away with it, but he had the best pitch ever. Bauer is a very good pitcher, but not so good he can just coast along throwing curveballs. Literally nobody could do that, because you need to throw other pitches for the deceptive aspect of the pitch to work.

So why did it work? Well three of them were pretty damn filthy. I’d have swung. But I’m terrible at baseball. Lamb is good though, and he swung too. So I am vindicated. Lamb also had seen the rest of Bauer’s repertoire in the previous two at-bats, so he had to look for a little bit of everything. Bauer didn’t give him any trends to go off. Since all he’d seen were essentially fastball variants, the most non-fastball pitch there is worked wonders against him here. Also, each pitch that Lamb swung and missed at was in nearly the same location - inside and at his back foot. It’s looking pretty plain that is a place he is vulnerable.

Even so, it’s even quite daring that Bauer kept going to it (or Perez called for it, depending on who made the decision each pitch) with a guy on third. This was after Bauer had given up a home run, and the Tribe was in the process of stranding a billion men on base. Any one of those pitches could have skated away and allowed a run to cross. Perez has such faith in himself, and Bauer in Perez, that both were okay with just going after it time and again.

It was neat though, and if you wanted you could look at it as a great case of a pitcher making a batter overthink, or just the power of the curve in a world where increasingly the curveball isn’t used. For years since the slider became a pitch, people migrated toward it since it’s easier to master. It even had the nickname “nickel curve” because it was a cheap version.

The curve is making a comeback, but right now the league is filled with young hitters that rose through the minors never having to deal with it. Without Lamb giving a pitch-by-pitch breakdown of the whole at-bat and what he was thinking, we don’t know why he was so fooled. But fooled he was. Shortly after that Bauer gave up a triple to Yasmany Tomas and soon found himself pulled from the game. But for this one at-bat, he unconventional and he was brilliant.