The Peralta Predicament

The Brewers announced last week that Freddy Peralta had made the Opening Day rotation. He competed for the spot with Josh Lindblom and dazzled in spring training to earn the chance to pitch every fifth day. His stock is quickly rising, but some have questioned how capable he is as a starter versus his prowess as a reliever. It’s no easy task figuring out how well Peralta’s stuff will translate as a starter, but he has shown a history of being able to start as a prospect. Though his performance in 2020 led many to believe they could form the most dominant trio in a bullpen this season with Josh Hader and Devin Williams. The Brewers have themselves a stud pitcher, but how will they use him? 

 

History as a Starter

 

The Brewers’ young starter has spent most of his professional career as a starter. It was only until 2019 that the team made him a primary reliever. In his minor league career as a starter, Peralta hovered around a 3.50 ERA and a K rate close to 30%. Both of those will get you a pristine reputation, and that helped fuel his rise as a prospect. Peralta’s problem has always been command. He usually had a double-digit walk rate in a season as a starter and that limited how deep into games he could work. If he wants to take the next step, that’s where he will need to grow. 

He’s only had one full MLB season as a starter. He finished that season with a 4.25 ERA with 96 strikeouts in 78.1 innings. It was a solid opening campaign for the rookie starter, who showed great potential in his peripheral statistics. He had a 3.72 FIP and 3.99 SIERA over that season as well. The area where Peralta excelled was getting swings and misses. Peralta had a 27.6% CSW and 10.8% SwStr rate. Now, that SwStr% is only a touch over league average, but consider the fact that Peralta was a two-pitch pitcher as a starter and was only 22 at the time, that’s mighty impressive for a young starter. The important thing to remember is that development isn’t linear but Peralta needed to improve on a few things if he were going to make it as a starter. 

The first and most obvious thing was his command. Peralta had a 12% walk rate in that season. He had a 49.4% zone rate, so he was around the zone a lot, but he wasn’t able to put away guys and get them to chase his curveball out of the zone to finish them off. That metric will likely get better as he improves his stuff and offers more looks to hitters. Peralta had a change-up, but rarely threw it and then scraped the pitch for a slider. I’ll dive deeper into both of those things later in the article. The final thing is to get more balls on the ground. Peralta’s fly ball rate was higher than his groundball rate. He can survive in the NL Central with that being the case but for more long-term success, he’d want to get that number down. In 2019 and 2020, Peralta was in the bullpen and improved in practically every one of those areas.

 

Bullpen Success

 

Freddy Peralta made just nine starts over the past two seasons but appeared in 54 games. His ERA skyrocketed in 2019, but that was because of three bad starts throughout the first few months of the season. Peralta had a few blow-up games and that cost him early, causing him to get sent down by the team. It’s possible his injury was nagging him early on and that caused him to struggle. But, Peralta’s walk rate dipped, his zone rate increased, and he was getting ahead of more hitters than before. He remained a two-pitch pitcher, for the most part, barely offering his change-up to hitters and relying heavily on his fastball and curveball. His O-Swing% increased as well and his SwStr% went up by almost two points. Both of those were great signs of future long-term success. 

Moving into 2020, Peralta grew even more. He had the lowest ERA, FIP, xFIP, and SIERA of his career. He struck out almost 38% of the hitters he faced while maintaining a 9.6% walk rate from the year prior. What was strange though was that his O-Swing% stayed relatively the same, while his zone rate and first-pitch strike rate fell dramatically. The biggest difference his O-Contact% fell by almost 15 points. He kept getting the same swings on pitches out of the zone, batters were just missing more of them. A big reason for this could be the introduction of a new pitch, his slider. He didn’t throw the pitch a ton, but it has similar characteristics to his curveball, which could have thrown hitters off. Plus, his curveball registered a whiff rate over 50%. He sacrificed some drop on the pitch to get more movement horizontally. His ground ball rate continued to climb and according to Baseball Savant, he had a higher ground ball rate than his fly ball rate. Another great sign of development. All of those things led to the issue we have today, should he stay in the bullpen?

His success in the bullpen in 2020 may make you believe that. It’s also fair to say that since he’s relied heavily on two pitches for the bulk of his career, he profiles much better as a reliever. They combined to strike out 43% of the hitters they faced in 2020. That’s appealing for a team to keep that core together at the back end of the bullpen to close games down. All three of them could work multiple innings too and in the postseason, could prove vital to their success. The issue for me is that he is only 24 years old now. Switching him to a full-time reliever so early in his career could hamper his development. His ground ball rate improved, his chase rate improved, he was getting more strikeouts while maintaining his walks, all of those things are good. Why not see what he can do as a starter? Especially if he can develop a few more pitches.

 

Can He Change It Up?

 

As already mentioned, Peralta is primarily a two-pitch pitcher. He has thrown a change-up in the past, but dumped it for a slider moving into 2020. The slider remains a part of his arsenal and looks to be seeing more action as he featured quite a bit in spring training. Here’s a look at strikeout featuring that very pitch. 

Freddy Peralta, Disgusting Slider. 🤮@ReviewngTheBrew pic.twitter.com/exz6A5mmAb

— Rob Friedman (@PitchingNinja) March 26, 2021

The slider offers a similar look to his curveball which can be seen here. 

https://gfycat.com/apprehensivepointlesscoati

They come out of the hand in roughly the same spot, have similar velocity while having slightly different movement profiles, which can make it tough to hit. Starting with his curveball, as I mentioned he sacrificed the drop on the pitch to get more horizontal movement. His 8:45 spin direction represents that approach. He has a 62% active spin rate on the pitch, which is within the standard range of a curveball that we’d expect. The way his slider moves, it might be recommended to get more drops on his curveball; it’s an issue that I wrote about with Dustin May here.

The difference, though, is Peralta has a lot of success with his curveball moving like that, all the more reason to keep it. His slider has a similar spin direction and offers above-average drop but below-average horizontal movement; opposite of his curveball, but it’s because he’s trying to get the pitches to play off of each other more. If he’s going to throw his slider more this year, which I believe he should if it’s moving as we’ve seen throughout spring training, then he should try to get a pitch that has a lot of downward movement. 

I think Peralta should bring back his changeup. The pitch never registered an unreal whiff rate or has any real statistical reason to throw it more often, but it would be a good opportunity to give hitters multiple different looks. Peralta’s fastball has good enough active spin to create good rise on the ball, and developing a change-up to play off that pitch would make Peralta even better. Like I’ve said in the past, though, when it comes to pitch design, we don’t need to overthink things. If Peralta has success with an increased slider usage, then there’s no reason to develop a fourth pitch beyond that if he doesn’t want to. 

I think Peralta is primed for a big year because of the success of his slider this spring and his curveball in 2020. I know some are worried about the possibility of his command faltering as he works later into games, a valid concern given the track record, but the Brewers are a well-positioned team to overcome any of those potential issues. Another reason to buy into Peralta this year, he won’t be asked to be their ace. Potential Cy Young dark horses Brandon Woodruff and Corbin Burnes will be in front of him in the rotation. It’s a lot easier for a young pitcher to pitch well when they aren’t asked to take a leading role early in their career. Peralta has all the stuff to succeed as a starter, if he can continue to increase his chase rate, lower his walk rate, and get more balls on the ground, then Freddy Peralta is here to stay and dominate the NL Central.

Photo by Dan Sanger/Icon Sportswire | Adapted by Doug Carlin (@Bdougals on Twitter)