"That was the plan going in, just a normal bullpen you would throw in the middle of a season or Spring Training," Gray said. "There weren't any limitations or anything."
It's unclear just how many rehab outings Gray will need once he's cleared for game action, but the expectation all along has been that he'll be back in the rotation by the end of the month. For now, the A's are fielding a rotation that's largely inexperienced, with just 16 starts between their Nos. 3, 4 and 5 starters combined.
Last year, Gray spent time on the disabled list twice for the first time in his career, and he said the experience offered a valuable lesson.
"I'm anxious to get back, but at the same time, after going through this a little last year, I understand that maybe one more week, or an extra bullpen, or an extra couple days on the front end, could really benefit you on the back end," Gray said.
"I think we're all on the same page as far as that goes and really making sure I'm 100 percent ready to get back out there in a big league game."
Gray's effort level, at least, is already "100 percent, for what you can do throwing in the bullpen," A's manager Bob Melvin said.
"There's a little bit more intensity throwing to hitters, and then in games, so there's an incremental portion to that. But if anybody can go as close to 100 percent in the bullpen, it's him."
• Chris Bassitt is scheduled to face hitters Wednesday for the first time since undergoing Tommy John surgery. The A's anticipate the right-hander returning as soon as June.
• Shortstop Marcus Semien stopped by Alta Bates Summit Medical Center in Berkeley on Tuesday to help welcome babies born on Opening Day into the A's family. All babies born Monday received an A's-themed newborn gift set and tickets to the A's home opener in 2018.