The Oakland Athletics are red-hot, but they suffered a major loss on Wednesday.
Blake Treinen, the club's setup man, is done for the season with a back injury.
He's tried to play through the injury over the last few weeks, but an MRI revealed a stress reaction.
Treinen pitched to a 4.91 ERA in 58 2/3 innings this season, after posting a 0.78 ERA in 2018, but he had been much better of later. Eight of his last 11 appearances were scoreless.