"I definitely felt like the ball was coming out really well," Gray said. "It felt pretty free, nice and easy.
"I feel like my stuff, just talking to the hitters, it seemed to be coming out really well, just late life, which is kind of trying to get back to where I want to be."
Gray is scheduled to throw a bullpen session Thursday morning ahead of the club's afternoon flight to Houston. Whether he's on the team charter could be determined that day. A's manager Bob Melvin said Gray's subsequent step would either be a simulated game on the road with the team, or a rehab assignment elsewhere.
"Hopefully after that," Melvin said, "he's back with us."
Gray posted a dismal 6.19 ERA in his first nine starts that preceded his first career DL stint, and there's thought that the injury was contributing to problems with the right-hander's arm slot and extension, resulting in command issues.
Gray said he's already felt a difference in his mechanics since undergoing week-long treatment.
"It wasn't as much manipulation and trying to do things that I normally don't do, so overall I think it went really well," Gray said. "I know my body feels really good now, and there's a little bit more rhythm in my delivery. I can feel that for sure. That's something that we've worked on in my last bullpen and even today, getting a little more rhythm and momentum toward the mound. I definitely feel a difference in that. I just feel like the ball is coming out like it always has."
"Free and easy, a lot of late movement, I know he felt pretty good about it too," Melvin said. "You could tell, as far as his arm action, movement on the baseball, he was throwing the ball free and easy, and that's what we're looking for at this point. So I think it went as well as we can expect."
Among the hitters to face Gray? Bench coach Mark Kotsay.
"He beat one into the ground I think," Melvin said, grinning.
• Left-hander Rich Hill (groin strain) is scheduled for a bullpen session on Wednesday, at which point the A's will determine when to slot him back into the rotation.
• Right-hander R.J. Alvarez (elbow surgery) will throw one inning with Class A Advanced Stockton on Friday in his first Minor League rehab outing.
• Righty Zach Neal was optioned to Triple-A Nashville to make room for Tuesday starter Eric Surkamp.