The Chicago Cubs made the move that fit their moment: they traded for David Peterson on June 25, 2026, and sent first base prospect Cole Mathis to the New York Mets. To make room on the 40-man roster, Chicago designated righty Yosver Zulueta for assignment.
The timing tells the story as much as the names. The Cubs had taken the first three games of a four-game series at Citi Field, and they were doing it with a rotation held together by necessity. David Peterson joins a staff that had already lost Cade Horton for the season, with Jameson Taillon out beyond the All-Star Break, Justin Steele unlikely to build up enough to matter as a starter, and injuries also hitting Edward Cabrera and Ben Brown within 24 hours of Jed Hoyer saying the Cubs were exploring the trade market for depth arms.
For Chicago, Peterson is not a clean bet so much as a needed one. He was carrying an $8.1MM salary in his final arbitration season, and he arrived with a 6.09 ERA across 68 innings after giving up five runs in four innings against Philadelphia over the weekend. The numbers behind that line are mixed in the way front offices often have to be with midseason pitching: a 19.7% strikeout percentage, a 9.4% walk rate, a 51% ground-ball rate and a.350 average on balls in play. That profile explains why the Cubs were willing to keep looking even while he was still finding his footing.
Peterson’s appeal is also in what he has shown before. He took the mound at Truist Park in the 2025 All-Star Game, posted a 2.91 ERA in 2024 and had a 3.06 mark in the first half of last season before a rough finish that pushed his ERA to 6.34 over 12 starts. Over the last calendar year, he had a 5.84 mark in 146 innings, which is not the résumé of a front-line answer but is enough to tempt a team short on arms and searching for innings it can trust.
The trade also says something about the Cubs’ priorities right now. They did not pay for certainty. They paid for a starter who can absorb innings while the Cubs standings chase keeps tightening and the rotation stays thin. What remains unclear is how quickly Peterson will be pushed into the Cubs’ starting staff, but Chicago has made its choice: it would rather sort out the rest of the innings later than keep waiting for healthier days.
