2023 Season in Review: Angel Zerpa

Angel Zerpa looked impressive for the Kansas City Royals in 2021 and 2022, despite only pitching a handful of innings. His 2021 ERA was 0.00 over five innings and he followed that up the next season with a 1.64 ERA over eleven innings. Heading into 2023, there was optimism that those results could continue over a larger sample of work. Kansas City was in dire need of starting pitching, and the door looked wide open for Zerpa to claim a spot after returning from injury this season.

Unfortunately for Zerpa, he did little to take one of those spots and there are now substantially more questions about his future as a prospect.

A look back at Angel Zerpa’s 2023 season

The season started off on a bad note for Zerpa after being placed on the injured list in spring training. The Royals placed him on the 60-day IL with left shoulder tendinopathy. He would remain on the injured list until June 15 when the organization sent him on a rehab assignment to Northwest Arkansas.

He only pitched eight innings for the Naturals with a 1.64 ERA before his rehab assignment was bumped to Triple-A Omaha. Zerpa pitched for the Storm Chasers for a little more than a month, from June 28 until August 1. While there, he logged 26.2 innings with a 4.73 ERA. Unfortunately, his strikeout rate was down and his walk rate was much higher than we’d seen from him previously.

Once August rolled around, Zerpa was recalled to the Major League roster and went on to make 15 appearances for the Royals in 2023. August would prove to be a struggle for the young lefty. He allowed 18 earned runs over 23 innings, good for a 7.04 ERA. He allowed five home runs and struck out just 6.7 hitters-per-nine-innings. Things looked much different for Zerpa than we had seen in the extremely small sample sizes in seasons passed.

In September, however, things looked a bit brighter. His best outing of the season came on September 15 against Houston, when he pitched four innings, allowing just two hits, one run, and one walk while striking out five Astros. Just a couple of outings later on September 30, Zerpa went 3 ¹⁄₃ scoreless innings against the Yankees, striking out five. That final outing of the year put the finishing touches on a very strong month of September. In all, Zerpa finished the season’s final month with 19 IP, 19 strikeouts, two walks, and a 2.29 ERA.

Where does Angel Zerpa fit into the Royals' future plans?

Despite the up-and-down season, Zerpa is still just 24 years old and won’t hit arbitration until 2026. He’s shown promise in each major league season thus far into his career but the injury bug has hampered his chances at sustained development. Kansas City is in desperate need of starting pitching, but it’s unclear whether Zerpa can succeed in that role. His best month this season came as a reliever.

Regardless of his role moving forward, the best path forward must include efforts to limit hard contact. Zerpa didn’t pitch enough innings to qualify, but if he had, Baseball Savant grades him well below average in a number of key metrics. Opponents posted an average exit velocity of 90.4 mph against him. He allowed a hard-hit rate of 45.5% and finished well below average in chase rate, whiff rate, and strikeout percentage. Where Zerpa succeeds most is in limiting free passes. That good command can only take a pitcher so far when hitters have so much success barreling up the baseball.

The “stuff” isn’t all bad, however. Based on velocity and pitch movement alone, Baseball Savant compares Zerpa to Tarik Skubal, Trevor Rogers, and Matthew Liberatore in 2023. With such good velocity and pitch movement, it gives the Royals pitching development a good foundation to continue growth with their young pitcher. Hopefully, 2024 will be a healthy season for Angel Zerpa, which could give him a chance to take some steps forward and truly find his place at the next level.