David Peterson gets the win in Cubs debut

Peterson’s second start as a Cub did not go nearly as smoothly as his first. He allowed three runs apiece in each the second and third innings on his way to an ugly 10 spot. That rally in the second was the most frustrating because Peterson retired the first two batters he faced and had the Cardinals’ seven, eight, and nine hitters coming up. Suddenly, a double, single, and homer turned into three runs. Similarly, before being yanked in the fourth, he got two quick outs and then proceeded to walk three consecutive batters. Then he was pulled after a run-scoring single and reliever Bryse Wilson gave up a home run to let that last two inherited runners score. In the end, Peterson had poor command and was hit hard just like in many of his other starts this season.

It’s a decent spot for Peterson to make his Cubs debut since Milwaukee ranks 22nd as a team in OPS against left-handed pitching this season. The 30-year-old southpaw was acquired from the Mets to shore up Chicago’s injury-ravaged rotation earlier this week. His immediate fantasy appeal is strictly limited to deeper mixed leagues given his struggles this year, but it’s possible a change of scenery helps him get back on track.

Peterson joins a beleaguered Cubs’ rotation to provide some stabilization, but it’s worth noting that he’s been far from a reliable option for most of 2026 with a 6.09 ERA and 1.65 WHIP over his 68 innings with New York prior to the move. The left-hander has had success in the past prior to this year’s scuffles, and because of the litany of injuries to the Chicago staff, he’s going to be given some runway. He should make his debut for the Cubs in the coming days.

Peterson provides Chicago’s injury-ravaged rotation with an immediate injection after struggling to a career-worst 6.09 ERA, 1.65 WHIP and 63/30 K/BB ratio across 68 innings for the Mets this season. The 30-year-old southpaw could certainly benefit from a change of scenery and should get an extended run with the Cubs who lost both Ben Brown (neck) and Edward Cabrera (hamstring) to the injured list earlier this week in addition to missing Cade Horton (elbow) and Jameson Taillon (hamstring) already. The Athletic’s Will Sammon adds that first base prospect Cole Mathis, who has posted a .981 OPS in the lower minors this season, is heading to the Mets in the deal.

Scott is eligible to come off the injured list on Saturday, which would bump Kodai Senga back a couple days or out of New York’s rotation entirely. It’ll be David Peterson handling Friday’s series opener. The 27-year-old will wind up missing only a pair of starts after hitting the injured list with a hip impingement earlier this month. He had allowed three earned runs or fewer in eight consecutive starts prior to being tagged for four runs over 4 2/3 innings by the Cardinals during his last start before landing on the shelf. He boasts a strong 3.10 ERA, 1.35 WHIP and 47/19 K/BB ratio across 40 2/3 innings this season. He’s a decent streaming option for fantasy managers in deeper formats where he may have been dropped.

Peterson walked back-to-back batters to start the game, which set the tone for the evening. The southpaw ran a ton of deep counts and it ultimately cost him. His biggest downfall was a three-run homer off the bat of Kyle Schwarber in the second inning. Peterson struck out five and walked four in the loss and now holds a 6.09 ERA on the year. He didn’t exactly make the case to get more starts in the near future, but the Mets aren’t exactly overflowing with options at the moment.

He’s getting the nod over Tobias Myers, who gave up seven runs in 1 1/3 innings against the Reds on Monday. Peterson last started on May 26, when he surrendered six runs in five innings against the Reds. He has a 5.91 ERA in seven starts and eight relief appearances this season.

Good grief. Starter, reliever, bulk pitcher, it doesn’t matter which role the Mets deploy Peterson in, he simply does not have it. He entered the game in the second inning and evaded trouble despite allowing two quick hits. Then, Nelson Velázquez and Jordan Walker each homered over the next two frames to put five runs off the board and another Cardinals’ rally in the fifth sent Peterson to the showers. Right now, Peterson has poor stuff and worse command. He and his 5.75 ERA should not be considered in any leagues.

Sean Manaea will be given the opportunity to work as a bulk reliever, likely behind an opener, in Peterson’s spot in the rotation beginning on Monday. The last straw for Peterson appears to have been giving up six runs on 11 hits over five innings against the Reds on Tuesday. He holds a miserable 5.57 ERA and 1.67 WHIP across 53 1/3 innings on the season.

The Mets have Jack Wenninger pitching quite well in Triple-A and might want to give him a chance in Peterson’s spot after this. Peterson is 3-5 with a 5.57 ERA, even though he’s allowed just two homers in 53 1/3 innings. His main problem is a ridiculous .376 BABIP. It was .579 tonight, even though he allowed just six hard-hit balls and had an average exit velocity of 85 mph. If he stays in the rotation, he’ll face the Mariners next. That Seattle has struggled mightily against lefties this year will probably buy Peterson a little more time.