Grading the 2023 KC Royals: Jonathan Heasley falls off the cliff

The Royals hurler did not have the season the franchise envisioned.

/ Eric Hartline-USA TODAY Sports

Welcome back to Kings of Kauffman's offseason series analyzing the 2023 performances of various KC Royals players. Today's subject is pitcher Jonathan Heasley.

Jonathan Heasley entered 2023 on shaky ground. The KC Royals viewed this past season as an evaluation year, but they already had a fair amount of tape on Heasley. He was solid as a September call-up in 2021, but while he showed flashes as a starter in 2022, he failed to consistently produce over 21 starts. Following an unimpressive spring, he started 2023 in Omaha, where the Royals hoped to prepare him for a new role out of the bullpen.

Heasley gets the call, but his answer leaves KC Royals with more questions.

Heasley breezed through much of the minor leagues in his first go-around, but his second tour of duty in Omaha didn't go so well. He pitched in 32 games, starting 15, and posted a 2-5 record with an ugly 6.85 ERA and 1.62 WHIP. But when your bullpen is as unreliable as the Royals' was this season, such a performance doesn't rule out a big league call-up.

The Royals brought Heasley up on May 5, and he pitched 2 2/3 innings in relief of a scuffling Brad Keller during an embarrassing 12-8 loss to the Oakland Athletics. Heasley gave up four hits and two runs, which was better than Keller's line, but hardly inspiring. The good news was that this turned out to be his worst performance of the season. The bad news is that it never got a whole lot better.

Kansas City sent him down after his lone May appearance, but he returned to the big league roster on the Fourth of July and pitched relatively well, striking out two and holding the Minnesota Twins scoreless in an inning of work. It was one of only five outings this year where he did not give up a run, and all five of those came within his first seven appearances back in the Show. Translation: the good times did not last.

Heasley is a tantalizing prospect because he has good stuff. Armed with five pitches, his four-seam fastball has a high spin rate and good movement, and his curveball and slider have the look of highly effective pitches. Unfortunately, those things have never translated to him getting guys out on the mound. He lacks command and gives up way too many home runs and walks, even if he did cut down on the latter — 1.2 BB/9 in 2023 compared to 4.1 BB/9 in 2022 — and he's shown a chronic inability to put batters away when he gets up in the count. Heasley is hardly the only Royals starter to struggle in this area, but his strikeout rate dropping from 6.1 SO/9 in 2022 to 5.4 SO/9 in 2023 didn't do him any favors.

After yet another shaky appearance in a blowout win over St. Louis on August 11, saw him hit a batter, gave up a two-run home run, and allowed another single before backing out of the ninth inning with a double-play. Heasley was sent back down to Omaha. He did not return to the majors in 2023. It remains to be seen whether he ever will, at least in a Royals uniform.

What grade did Jonathan Heasley earn in 2023?

Heasley's final 2023 numbers were: 0-0 in 12 games, 15 innings pitched, nine strikeouts, five home runs, 63 ERA+, 6.99 FIP, and a 1.267 WHIP. On the bright side, he somehow improved from -0.5 fWAR in 2022 to -0.3 fWAR in 2023. Yikes.

I'm tempted to give Heasley an F, but I'm going to give him a D-, because if I squint hard enough, I can still almost make out what the Royals saw in him when they drafted Heasley in 2018. But those flashes grow dimmer with each passing season. The Royals moved Heasley to the bullpen in the hopes that his stuff would play up in a way it never did as a starter, but that experiment was a flop in 2023.

It's possible we've already seen the last of Jonathan Heasley at Kauffman Stadium, but with the Royals' bullpen still looking for answers, I think he will get another chance to prove his worth as a reliever in the spring. He is working with Tread Athletics this offseason, which paid dividends for his teammate, Cole Ragans, and he will need to show that he's taken a colossal step forward right out of the gate if hopes to get another shot. If not, his enduring legacy in Kansas City may be that of the guy who once upchucked on the mound.

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