If Braden had been unable to make the start, lefty Dan Meyer, just called up from Triple-A Sacramento on Sunday, would have gotten the call.
Meyer took Dana Eveland's spot on the roster, with Eveland making the return trip to Sacramento.
Eveland took the loss Saturday, knocked around for nine runs (eight earned) on eight hits (two home runs) and two walks in two innings as the A's fell to the Red Sox, 12-2.
Geren said Eveland went to Sacramento with instructions for things to work on.
"Commanding the strike zone better -- really, that's it," Geren said. "He's throwing the ball low- to mid-90s with a good breaking ball. The stuff is there. Just repeating the delivery and being consistent in the strike zone is really all he needs to do. The physical ability with the pitches [is] there. We've seen him dominate at times, but consistency isn't there and this is a very tough league without consistently putting the ball where you want to. That's the main thing."
In 22 starts this season, Eveland was 7-8 with a 4.46 ERA. In 125 innings, he had allowed 126 hits and 64 walks, striking out 85.
"He was obviously a little bit disappointed," Geren said. "But this is the big leagues and really, you have to perform at this level. It's the top, the top league in the sport. So, he's right there. He's had success here before, and we expect him to have more in the future. But right now, he wasn't performing up to what we need."
Meyer has not appeared in a game for the A's yet this season. In 22 games (20 starts) for the River Cats, he is 10-5 with a 4.48 ERA. He faced the Red Sox once, last season in Boston, going two-thirds of an inning and allowing one run on two hits and a walk. On Sept. 25, 2007, he entered the eighth inning with one out, a runner on second and the A's trailing, 5-1. He gave up a two-run homer to David Ortiz before getting the last two outs.
In 2007 for the A's, Meyer was 0-2 in six appearances, three starts, with an 8.82 ERA. He will be the 44th player to appear in a game for Oakland this season. In 2007, the A's used a club-record 54 players. He will be the 15th rookie to appear in a game this season, after 17 made appearances last year.
Geren said it is possible Meyer could take Eveland's place in the rotation, with a potential start Thursday in Toronto.
"We're leaving all those options open," Geren said.