"I threw everything I had and wasn't holding back. It felt really good," said Gray.
A's manager Bob Melvin echoed Gray's comments, adding that the club will make a decision on if Gray will return depending on how he feels Sunday. It is still yet to be determined if Gray would start or come out of the bullpen.
"I know his routine would suggest he's used to starting. We'll see," said Melvin.
Gray doesn't have a preference on starting or relieving; he just simply wants to pitch.
"As long as I can be able to get out there, that's all that really matters," said Gray, who is 5-11 with a 5.74 ERA in 21 starts this season. "It's the next step in the rehab process. You work hard to get back into the game. Just because the season is coming to an end, doesn't mean that the next step isn't pitching in a game."
Gray said that returning to a game isn't a mental hurdle he wants to clear before the regular season ends. However, Melvin thinks appearing in a game-like scenario can have a positive affect for Gray heading into the offseason.
"No matter what you do on the side, it's not the same as a game," said Melvin. "Maybe not mental for him, if he feels like he's sound. I think it goes a little ways to get out there on the mound, do it in a game, and then go home and get yourself ready for Spring Training next year."
Justin Wise is a reporter for MLB.com based in the Bay Area. This story was not subject to the approval of Major League Baseball or its clubs.