Zach Thornton Shows Flashes, But Rough Debut Complicates Mets' Rotational Outlook

Zach Thornton's MLB debut was far from perfect, leaving a big question mark regarding the Mets' rotation. | Geoff Burke-Imagn Images

Well, Mets fans, any hope of Zach Thornton potentially sticking around as a legit option for the depleted rotation seemingly vanished. The 23-year-old was advertised as a pitcher with elite command and quickly moved through Triple-A Syracuse after just two starts. However, his first day in the majors wasn’t pretty, though it could serve as a learning experience.

Thornton took the mound for his debut in Washington, D.C., against the Nationals, with a chance to make a case for a rotation spot. The first at-bat went smoothly, forcing James Wood into a groundout, but what followed quickly shifted momentum. Thornton allowed a single, then issued a walk, before CJ Abrams launched a three-run home run on a hanging 85 mph fastball, putting the Mets in a 3-0 hole in the first inning.

CJ Abrams gives the @Nationals an early lead with a 3-run blast 💥 pic.twitter.com/z1XPQZPjBa

— MLB (@MLB) May 20, 2026

The left-hander settled down from there, striking out Dylan Crews and inducing a groundout to end the inning after a rocky debut frame. Not all the blame could be placed on Thornton, however, as catcher Hayden Senger missed several opportunities to use the ABS challenge system, extending at-bats that might otherwise have ended sooner. The disastrous night from the Mets catcher continued, submitting a throwing error in the second inning off a Nasim Nunez stolen base, allowing him to advance to third base, where he’d score moments later. 

Thornton would continue past his debut inning, but struggled to find a consistent rhythm as the outing progressed. The No. 13 prospect was struggling to put batters away and also force ground balls, with his pitch count eclipsing 58 pitches just after two innings. 

However, the rookie would settle down a bit, retiring eight-straight batters following the Keibert Ruiz second-inning RBI single, throwing just 18 pitches through the next two frames. Thornton would finish his evening going 4 1/3 innings, allowing four runs, four hits, while walking two batters and striking out three. 

"The one thing that I liked, even after he got punched there in that first inning, he didn't back down," said Mets manager Carlos Mendoza following the rookie's debut, via MLB.com's Anthony DiComo.

Mets' rotational outlook after Zach Thornton's MLB debut

Thornton’s performance complicates his immediate outlook, though he could still remain in the mix as the Mets continue to navigate a thin rotation with Clay Holmes on the shelf and Kodai Senga working his way back from injury.

No. 2 prospect Jonah Tong was scratched from his scheduled Triple-A start Wednesday, with manager Carlos Mendoza indicating the Mets could potentially use him this weekend in a three-game set against the Marlins.

Jonah Tong could join the Mets' rotation after being a surprise scratch this week. | Sam Navarro-Imagn Images

Tong previously received a brief MLB look last season during a stretch of pitching injuries, part of a broader youth movement that also introduced Nolan McLean and Brandon Sproat. The 21-year-old struggled in that stint, posting a 7.71 ERA across five starts while also issuing nine walks.

This season in Syracuse, Tong has continued to battle inconsistency, posting a 5.68 ERA over nine starts and allowing six runs while recording just 1.2 innings in his most recent outing.

Other options remain available. Tobias Myers, acquired as part of the Freddy Peralta trade, has been effective out of the bullpen this season and has prior experience as a starter in Milwaukee. Through 29 innings, the right-hander holds a 3.41 ERA with 23 strikeouts and six walks.

After nerves likely got the best of him in his debut, Mets fans will be eager to see what Thornton can do next. He has all the tools to be a big-league starter, and now it's time for him to prove it after getting his "welcome-to-the-MLB" wake-up call.