Mitch Keller's familiar second half adds another layer to Pirates' bold deadline decision

Keeping Mitch Keller instead of trading him at the MLB Trade Deadline was a very bold decision by the Pirates' front office. Their young pitching has been fantastic, but there have been no signs of an improving offense down the stretch. It's not exactly fair to say the Pirates were solely responsible for Keller remaining in Pittsburgh, though. There are a handful of factors at play that likely made other teams conservative in putting together a deal for Keller, and onered flag has waved dramatically recently.

One of the biggest concerns surrounding Keller was his history of inconsistent second halves. Throughout his career, Keller has struggled badly following the All-Star Break, posting a 5.13 ERA in that period. That trend has continued in 2025, as he currently owns a 5.73 ERA with a 1.50 WHIP. For any team fighting down the stretch for a spot, preparing to absorb a long-term contract like Keller's, that is obviously a concerning trend.

Almost all the traits that have gotten Keller to 12th in baseball in quality starts have collapsed in the second half of the 2025 season, too. His BB/9 has climbed from 2.04 to 3.33, and his HR/9 jumped from 0.68 to 1.66. Everything has inflated for him, which was somewhat expected, given what he has proven in his career. That concern likely stunted his value, and was the cherry on top as trade talks stalled.

Mitch Keller's shaky second half just adds on to why the Pirates couldn't find a taker

Considering the amount of young pitching in the Pirates organization, taking the gamble on all of them at one time could have been a dangerous experiment. Putting the pressure on a young prospect to fill in for Keller immediately, let alone next season, would be a lot to place on a young prospect's shoulders. Keller is an All-Star who has made 30 starts a season or more for the past four years. After watching the inconsistencies from Bubba Chandler, things could have been even worse (and even more strain could've been placed on the bullpen) without a consistent innings-eater present.

Additionally, Keller's contract wss also a trade blocker. While money isn't really a problem for most contenders out there, he is still an expensive player to add in the mix of a season, with years to go. If he struggles or regresses, you're stuck with his contract. Teams are definitely hesitant to add an expensive arm like that, especially considering his ineffectiveness down the stretch of the season.

Plus, the Pirates are obviously not sending money over to pay for him. They can barely afford a roster of three guys earning above $10 million, let alone paying someone who wouldn't be pitching for them. They'd be handing over a financial burden to someone else without receiving a substantial package in return, given they'd have prioritized tax relief over prospect upside.

There were so many factors that prevented a Keller trade. With all of these negative factors swirling, the Pirates would have gotten another trade package in return that fans would've groaned about. So, even though he has struggled, maybe holding on to him was the right idea.