May 31, 2024 at 9:00 AM
Scouting Scratch: The changes that have unlocked Luis Perales' potential
Coming into the year, Perales was seen as a volatile arm with impressive stuff, but held back by inconsistent command and performance. This year, Perales has been a different pitcher, showing improved command and consistency and dominating the South Atlantic League with 46 strikeouts to only 10 walks in 26.1 innings. His 3.42 ERA and 1.44 WHIP do not jump off the page, but those numbers are deceiving, illustrated by his 1.91 FIP and astronomically high .474 BABIP, that is largely due to a subpar Greenville defense. (A hiccup in his first start, in which he gave up three runs on three hits and two walks in one inning—but still struck out three—also accounts for nearly a full run of his ERA.) His strikeout rate has increased dramatically and his walk rate has dropped. He is generating much more contact on the ground and is giving up far fewer fly balls and home runs. Everything is trending in the right direction, and looking under the surface, several tangible changes that have allowed him to unlock this performance.
What’s changed in 2024?
Fastball velocity
While Perales is throwing the same four pitches, his velocity and usage have changed drastically. I saw Perales at the end of last year in Greenville and he was sitting 93-96 mph. In his eight starts for Greenville in 2023, his fastball averaged 94.7 mph. This season, Perales’ average fastball velocity has jumped around two mph, and in his final outing in Greenville last Monday, he sat 94-98 mph and maxed out at 99 mph. That increased velocity gives him a greater margin for error when he misses in the zone, but his command has improved as well, as he is throwing the pitch competitively more frequently and missing bats at an above-average rate with it.
Pitch usage
While the increased velocity has allowed Perales’ fastball to play up, a bigger change is how he is using his four pitches. This year, Perales is doing a great job mixing his pitches, using all four between 15% and 34% of the time. Last year, he was far more reliant on his fastball, with his slider getting by far the most use of his secondaries.
Perales’ most used pitch has been his cutter at 33.6%, up from 7.8% last year. He has developed much better feel for the pitch, and that has allowed him to decrease his fastball usage substantially from 62.0% last year to 27.6% this year. Getting ahead of hitters with his fastball was a struggle for Perales in 2023, but the shifts to his pitch usage have helped with that, as he has thrown the cutter in the zone substantially more often than his fastball this year (60% vs. 45%). By featuring his cutter, he is able to get ahead more consistently, generate more weak contact on the ground, and finish at-bats quicker. Although the pitch does not grade out as well with scouts as his other offerings, with some calling it average, it plays well off the rest of his arsenal and allows everything else to play up.
Perales’ fastball is a great example of that effect from the cutter, as even though he is throwing it less often this year, it is playing more effectively. He’s got a 34.5% whiff rate with the pitch—for reference, well above the MLB average of 22%. Even though he does not throw it in the zone as often as his other pitches or get called strikes with it (20% called strike%), that’s not as much of a problem when he is getting ahead with his other pitches and using the heater more as putaway pitch or as a compliment to his best secondary pitch, his changeup.
Increased changeup usage is the other big arsenal change for Perales, as the pitch has developed into his best secondary, playing very well off his fastball. (Note: I am calling it a changeup based on its spin rate and movement profile, but Baseball America refers to it as a split-change and the Red Sox call it a splitter). In 2023, he threw his changeup only 9.6% of the time, but this year that has increased to 23.4% of the time. With his fastball having elite shape, with 20+ inches of induced vertical break and playing best up in the zone, his changeup compliments the pitch perfectly with nice downward action, giving him a great north-south combination. So far this year, he’s got an absurd 58.1% whiff rate and 44.4% chase rate on the changeup, and scouts see it as a true plus, big league-quality out pitch.
The final change in Perales’ arsenal is decreased slider usage, albeit not to the same level as his fastball. Last year, it was his most frequently-used secondary at 20.6%, but this year it’s his fourth-most-used pitch at 15.4%. He has been able to land his slider in the zone consistently this year and still generate above-average whiff rates with it. Interestingly, the pitch is not getting hitters to chase much, but with how effective his other pitches—especially his changeup—have been in that respect, that is not a huge deal. His slider does not need to be a major chase option when he’s got the fastball and changeup to go to as put-away pitches; instead it can be used as another pitch to get ahead in the count and generate weak contact, which contributes to an increased ground ball rate and lower walk rate this year.
What’s next?
Evaluators who have seen Perales this year have been blown away with his stuff and now consider him the best arm in the system, with some suggesting that he should be on the national radar for top 100 prospect lists. He’s showing at least two plus pitches and all four are at least average. His promotion to Portland this week, with his Double-A debut set for Sunday, will be a great test for him, as the caliber of play in the low minors this year is poor, so someone with his stuff is expected to dominate. Regardless, having separated himself from the other arms in the system at this point, his development gives the Red Sox their highest-upside pitching prospect in some time.
Photo Credit: Luis Perales by Kelly O'Connor.
Ian Cundall is Director of Scouting for SoxProspects.com. Follow him on Twitter/X @IanCundall.