Balfour has not allowed a run in nine of his last 10 outings, and only allowed a single run in the other outing.
"First with Godfrey, we took him out of the rotation, obviously, with guys coming back. He was in the long role, [but] didn't get to pitch," Athletics manager Bob Melvin said.
The 26 year old was sent down in order to ensure he was pitching regularly, and would be able to come back up if any starters sustained an injury that he would need to fill in for.
"He was preparing and staying ready. But now, it has gotten to the point where he has to just go down and pitch," Melvin said. "Get his pitch counts back up, whether it's insurance on a starter or long reliever, or something along those lines."