SAN FRANCISCO — In the second-to-last game of the regular season on Saturday, the Dodgers lost their longest-tenured pitcher to a likely season-ending injury.

While warming up in the bullpen during the Dodgers’ 4-3 win over the Giants, veteran reliever Blake Treinen suffered a potentially serious shoulder injury, according to manager Dave Roberts.

Blake Treinen of the Los Angeles Dodgers pitches in the ninth inning at Dodger Stadium on Wednesday, September 23, 2026, in Los Angeles. Getty Images

While Treinen will go for imaging on Sunday, he is heading for the injured list and is not expected to return in the playoffs.

“I don’t know if it was a complete blowout, but really unfortunate,” Roberts said. “His season’s over, unfortunately.”

A 38-year-old right-hander who played key roles in each of the Dodgers’ three recent World Series titles in 2020, 2024 and 2025, Treinen has been plagued by arm issues the last two years. This season, he missed 2 ½ months with inflammation in his right elbow. Last year, he missed almost three months with a forearm problem. And after the 2022 season, he underwent a shoulder surgery.

The Dodgers had been trying to manage Treinen’s usage carefully since his latest return in early September, giving him just seven appearances in the four weeks he had been back.

However, he felt something on a single warmup during Saturday’s game. The pain was bad enough to send him straight back to the clubhouse alongside a trainer.

“It’s gut-wrenching for us,” fellow reliever Alex Vesia said. “Blake’s one of our leaders out there in the bullpen.”

Los Angeles Dodgers pitcher Blake Treinen throws during the second inning of a baseball game against the Cincinnati Reds, Wednesday, September 16, 2026, in Cincinnati. AP Photo/Carolyn Kaster

Treinen had already appeared to be a playoff roster bubble candidate previously, with a 3.64 ERA in 36 games this year. Still, the Dodgers had been encouraged by a recent uptick in velocity and were still hoping to have the 12-year veteran as a postseason option — especially given his 43 career games of playoff experience, highlighted by a heroic 2 ⅓-inning outing in their title-clinching victory in Game 5 of the 2024 World Series. 

Instead, his season — and, as a pending free agent, perhaps his Dodgers career, as well — now suddenly appears to be over.

“I saw him and hugged him,” Roberts said. “It’s just unfortunate.”