Mets Set to Promote Pitching Prospect After Just 2 Triple-A Starts

He made his Triple-A debut earlier this month

May 15, 2024; Philadelphia, Pennsylvania, USA; New York Mets logo on the sleeve of J.D. Martinez during a game against the Philadelphia Phillies at Citizens Bank Park. Mandatory Credit: Bill Streicher-Imagn Images | Bill Streicher-Imagn Images

The New York Mets are planning on calling up one of their pitching prospects for his major league debut later this week.

Left-handed pitcher Zach Thornton, New York's No. 13 prospect for 2026 on MLB Pipeline, is going to pitch for the Mets on Wednesday, manager Carlos Mendoza announced on Monday. Mendoza also said the team hasn't decided whether the 24-year-old will start or throw after an opener. But either way, the southpaw is scheduled to pitch on a major league mound this week for the first time in his career.

Thornton was just promoted to Triple-A on May 7. In two starts for the Syracuse Mets, the 2023 fifth-round draft pick posted a 2.25 ERA with 13 strikeouts and three walks in 12 innings pitched. And according to Mendoza, that level of command played a big part in the Mets deciding to call up Thornton rather than other top pitching prospects like Jonah Tong or Jack Wenninger.

Mets going 'one outing at a time' with Zach Thornton

Mar 15, 2026; Port St. Lucie, Florida, USA; New York Mets starting pitcher Zach Thornton (21) and catcher Francisco Alvarez (4) walk in from the bullpen before the game against the Toronto Blue Jays at Clover Park. Mandatory Credit: Jim Rassol-Imagn Images | Jim Rassol-Imagn Images

The Mets enter Monday's action still in last place in the National League East with a 20-26 record. But top outfield prospect A.J. Ewing was called up last week and instantly provided a spark for the struggling squad. Now, New York likely hopes Thornton can give the team's pitching staff a boost after losing Clay Holmes due to a fractured fibula.

Ahead of his big league debut, though, Mendoza made it clear that the Mets are going "one outing at a time" with Thornton. So, the southpaw's first MLB outing will effectively be an audition to determine whether he sticks around in the majors beyond Wednesday.

Either way, it is noteworthy that New York is calling up Thornton over Tong or Wenninger, who are the Mets' top two pitching prospects on MLB Pipeline. Tong made his big league debut last season and has 55 strikeouts in 38 innings pitched this year. But he also has a 5.68 ERA in nine Triple-A starts to begin 2026. Wenninger, on the other hand, has a 1.51 ERA through eight starts with Syracuse this year.

For now, though, Thornton will get the ball at some point on Wednesday, and his performance could directly impact whether the Mets turn to Tong or Wenninger after that.