Going into 2026, Zac Thornton wasn’t one of the Mets’ blue-chip prospects. But after he spent most of the first half of the year in the minors, he got called up in July and proved down the stretch why he belongs.

Thornton’s final start of the year was another solid one. He allowed two runs over five innings against the Texas Rangers on Thursday, giving up four hits while walking one and striking out four.

“It’s fair to say what he’s done…has largely exceeded expectations,” manager Andy Green said after the game.

Geoff Burke-Imagn Images

The only major damage Thornton allowed came in the first inning, when he surrendered a leadoff single. Two batters later, Josh Jung hit a two-run bomb. Thornton settled in from there, keeping Texas off the board over his final four innings.

Thornton still had to work through some trouble, though. In the fourth, Texas put two runners on with just one out. But he responded well, striking out Wyatt Langford and inducing a groundout from Ezequiel Duran to escape the inning.

It was once again an extremely composed outing from the rookie left-hander.

That composure has become one of Thornton’s clear calling cards. He has rarely looked overmatched by opposing hitters, as he has been relying on his pristine command. His outing Thursday showed that composure, as he recovered from the early home run and kept the game close.

Thornton finished his rookie campaign with a 3.42 ERA and 1.14 WHIP across 84 1/3 innings and 15 starts. He struck out 63 while walking just 18 for a solid 3.5 SO/BB ratio.

Still, Thornton doesn’t believe his success came out of nowhere.

“I always thought I’d be up here this year, I didn’t know to what extent it would be,” Thornton said. “I wouldn’t say I surprised myself. I feel everywhere I’ve gone to pitch I’ve succeeded.”

There are still areas for Thornton to improve. He isn’t an overpowering strikeout pitcher, and the long ball hurt him at times in the year. Thornton said one goal for next year is to raise his fastball velocity into the 94-96 mph range.

In such a disappointing season for New York, Thornton was a pleasant surprise. Along with Nolan McLean, Christian Scott and Jonah Tong, he has become part of a promising young rotation that should be extremely important heading into 2027 and beyond.

“What you saw on the field, just a small sample size,” Thornton said. “All four of us are going to get better.”