Hahn has a history of arm-related issues, considering he’s already had Tommy John surgery once in his career, so it’d behoove the A’s to proceed with caution. They had hoped to have him back in the starting rotation shortly after the second half began, but that obviously won’t be the case anymore.
Beane touched on that aspect of the situation when speaking with Hickey, saying, "We’re going to be conservative with Jesse. And the tough thing with is starters is once they’re shut down, it take a while to build back up. So it’ll be longer rather than shorter. But Bassitt has come in and pitched very well and kept us very much in the game, so that’s been good."
Chris Bassitt stepped in for Sonny Gray a few weeks back when Gray was battling bacterial gastroenteritis and pitched well, and he’ll apparently have more opportunities to pitch well now that he’ll take the ball in Hahn’s place for the next few weeks (at least).
So far in 2015, Hahn has a 6-6 record and a 3.35 ERA, and had been on a bit of a personal hot streak before these new issues flared up.