Is Freddy Peralta a Better Pitcher With Gary Sánchez Behind the Plate?

Freddy Peralta has pitched to William Contreras in 22 of his 26 starts, but Thursday afternoon saw him paired with Gary Sánchez for the second outing in a row. It also became the third time this season that Peralta has allowed no more than one earned run in consecutive starts.

After blanking the Cardinals over five innings, Peralta has now posted a 1.17 ERA in four starts with Sánchez, compared to a 4.37 ERA with Contreras. ERA often does not tell the whole story of a pitcher’s performance, though, especially in a small sample. Most evidence points toward Peralta being the same pitcher regardless of his batterymate.

Peralta has pitched to a 4.17 FIP with Contreras. With Sánchez, that figure is 4.34. Furthermore, there is minimal evidence suggesting that he’s been any better pitch-to-pitch when paired with the latter. If anything, there are some signs that he has not been his best self in those starts.

Sánchez follows the same blueprint that Contreras does when calling the game for Peralta. He has thrown fewer sliders and more curveballs to Sánchez, but Peralta attributed that to not having a feel for his best breaking ball in his start on Thursday. With that in mind, the breakdown is nearly identical.

Unsurprisingly, using a similar mix with similar execution means Peralta’s pitch results have not substantially improved. He’s allowed less hard contact in Sánchez starts, but is also inducing fewer swings and misses and chases outside the strike zone.

The real takeaway is the lack of discernible improvement to Peralta’s pitching with Sánchez beyond his shiny ERA. Most notable on that front is that his greatest weakness of failing to put hitters away more efficiently remains unchanged.

Peralta is essentially averaging the same number of pitches per batter faced with Contreras and Sánchez. According to TruMedia, he’s thrown pitches in non-competitive locations (more than 18 inches away from the center of the strike zone) at a slightly higher rate when caught by the latter. The issue remained pronounced on Thursday, as Peralta reached nine three-ball counts, inflating his pitch count to 92 in those five innings.

Maybe, maybe, maybe there's one thing here, if we want to get very granular. Against right-handed batters, both Sánchez and Contreras have called a similar percentage of changeups for Peralta. However, while most of those pitches have ended up on the inner third to righties with Contreras behind the plate, more of them have been away with Sánchez there. 

The arm side of the plate, where the majority of even right-on-right changeups have landed with Contreras and Peralta working together, is the natural place for that pitch to go. It's in the nature of a changeup to fade in that direction; that's why the pitch is usually thrown principally against opposite-handed batters. When you have a power changeup like Peralta's, it's also not a bad idea to steer it in under the bat paths of some hitters.

The location differences here could be random, given how small Sánchez's sample is, and they don't automatically imply one approach being superior to the other. However, in two directly comparable moments, we can see an important difference. Here's a 2-2 changeup Peralta threw to Atlanta's Austin Riley on Jul. 31, with Sánchez behind the plate.

That's a hard-hit ball, and Willy Adames's fielding burp ensured that it didn't have a happy ending for the Brewers. Still, it's a ground ball. It's an out, most of the time. Note the way Sánchez set up for the pitch. He got low, and his mitt placement led Peralta to get the ball away from Riley. 

Here's a 2-0 changeup Peralta threw Riley one week later, in suburban Cobb County, Ga.

That's a very different setup from the catcher, and a very different pitch location--with a very different result. Every pitcher has a different set of preferences about how their catcher sets targets, and not all of their preferences are rational, or even important. It can be one underrated factor in the command a pitcher demonstrates, and one small way a catcher influences a pitcher even if they call the game and frame pitches about the same way another catcher does. Even so, this is anecdotal, and it's not quite enough to say for sure that Sánchez takes a different tack with Peralta than Contreras does, for better or worse.

There does not appear to be anything in particular about the Peralta and Sánchez pairing that has brought out the best version of the former. Rather, he’s performed at a similar level while enjoying better sequencing with the latter behind the plate. If Sánchez continues to team with Peralta more often, expect the results to even out.