The left-handed Doolittle, rehabbing a sore shoulder, first threw to hitters on Friday. On Monday, he said, "I feel like the effort level was probably even a little more than the other day."
"I was throwing pretty much as hard as I could, just like I would in a normal game," said Doolittle. "Twenty-three pitches is a lot, and usually if I'm throwing 23 pitches in an inning we have problems, but I still felt like the last five or six I threw, I had enough in the tank to reach back and get a few by [Mark] Canha."
Opponent Josh Phegley took notice.
"I think, last time I faced him, he felt like it was just another bullpen and he didn't really have that adrenaline," said Phegley. "Us getting some good swings off him, he said that maybe helped him get a little angry and get more intense about it. I think he came out that way today from pitch one."
Doolittle only threw fastballs on Friday, but he mixed in his slider and changeup this time around and was pleased with both, noting he felt extremely confident in the slider, even throwing it to right-handers.
Phegley homered off Doolittle's fastball but struck out on his changeup.
"I told the guys, 'His changeup, if he throws it for a strike, it's an out, and if he throws it for a ball, it's a swing-and-miss.' It's pretty good, especially off his fastball," said Phegley. "It looks just like his fastball and just falls off at the tail end. I thought he looked really sharp today."
• Ben Zobrist, nearly two weeks removed from left knee surgery, could be taking batting practice with the club as soon as Tuesday. He hopes to return to the A's lineup by June 1.
• Pitchers A.J. Griffin and Eric O'Flaherty, both dealing with shoulder soreness, were scheduled to see doctors Monday evening and could begin playing catch again by the end of the week.
• Right-hander Chris Bassitt was optioned to Triple-A Nashville on Monday to make room for newly acquired reliever Edward Mujica and is expected to return to the Sounds rotation.
Bassitt held the opposition to a .135 batting average in five relief appearances for the A's but issued nine walks in 10 2/3 innings.