After backing the left-hander David Peterson, the New York Mets are finally trading him away to the Chicago Cubs. The 30-year-old is in his 7th season with the team and has the worst numbers in his career. The Mets tried to revive his season in different ways. But they ultimately decided to cut ties with Peterson. 

New York has been stuck at the bottom of the NL East for the majority of the season. They are the only team below .500 (12 games behind) in their division. They are in dire need of some major changes. In that attempt, they have traded their longest-tenured player in exchange for 1B/DH prospect Cole Mathis from the Cubs.

David Peterson started his major league chapter with the Mets in 2020. He was the Golden Glove finalist and MLB All-Star last year. And the Mets signed a 1-year, $8.1 million deal with him this January. But the lefty hasn’t been able to replicate his success from the previous season. His 6.09 ERA is the worst since he joined the majors. 

In fact, his performance was declining in late 2025. He had a 6.68 ERA in August and 9.72 in September. Entering 2026, he started with a scoreless 5.1 innings, but that was his brightest spot of the season. Peterson has had a few other instances of scoreless pitching, but he has allowed 51 runs over 68 innings so far. The Mets even tried to shift him from a starting role to a reliever, but it didn’t help his cause. In fact, his June numbers have rocketed to 10.97. 

He had one of the most expensive outings on June 10 against the St. Louis Cardinals, allowing 7 hits and 6 runs in just 3.2 innings. Yet manager Carlos Mendoza chose to have his back. 

“He’s a good pitcher, and we’ve seen flashes, especially coming out of the bullpen as that bulk guy.” Mendoza addressed Peterson’s struggles. 

However, it seems that they have finally run out of patience with the pitcher, as they are sending him off to Chicago. 

Cubs see opportunity despite the struggles

Chicago has 12 players on the injured list, and 11 of them are pitchers. Justin Steele is sidelined because of left elbow flexor strain. He was initially expected to return by June 22. But he is still not fit enough, and MLB reports that he won’t be ready to start again before the end of this season. 

Ben Brown (1.85 ERA) has been great this season, but the team put him on a 15-day IL last night due to a neck strain. Edward Cabrera suffered the same fate on the same day because of his left hamstring strain. The Cubs’ No. 3 prospect, Jaxon Wiggins, has been out since April. 

Peterson isn’t joining a perfect rotation. But Chicago is willing to use his All-Star experience to boost the pitching department. They are 3rd in the NL Central with a 43-37 record and at par for a Wild Card spot. The 30-year-old might help their playoff hunt. 

The Mets aren’t getting a bad deal either. Cole Mathis is the Cubs’ No. 13 prospect with a .981 OPS. The 22-year-old is batting at .272 with 10 HRs in the minors this season. He can be a valuable younger asset for the Mets in exchange for a veteran nearing free agency.