Chapman took 30 swings off a tee on Friday, the first time he's hit since receiving another cortisone shot on Monday. Melvin said Chapman will take live batting practice on Sunday.
"If the cortisone does what it's supposed to do, [I'll] get ready to play real soon," Chapman said.
Chapman added that he received a second cortisone shot (he had his first in Spring Training) after a nerve injection a few weeks ago didn't work as expected. A bone growth in his hand is causing bruising and swelling in the thumb area, he said.
In 69 games this season, Chapman is hitting .250 with 10 home runs and 26 RBIs. In his absence, Jed Lowrie, the regular second baseman, has slid over seamlessly to third base despite not playing regularly at third since he was with the Astros in 2015.
Melvin said Chapman will be evaluated day to day, and a rehab stint remains a possibility. Chapman also said it's "hard to tell" right now whether he would consider surgery in the offseason.
"If it feels good one day, then we'll push it a little bit the next," Melvin said. "I think after Sunday, we'll have a better idea where the timetable is going to be."
Cahill progressing, Triggs shut down One injured A's starter is on the mend, while another hit a setback.
Trevor Cahill, who has missed his last few starts with a strained right Achilles, threw a 30-pitch bullpen session on Friday. He felt good, according to Melvin, who added that Cahill will throw either another lengthy bullpen or a simulated game soon.
The news was not so good for Andrew Triggs, who hit a bump in a road in recovering from nerve irritation in his right arm. The A's shut him down after he felt tingling in his fingers, and Triggs will get a second opinion early next week. He has not pitched since May 17.
Melvin pushes for Davis in Home Run Derby Melvin used to worry about his players ruining their swing by participating in the T-Mobile Home Run Derby, but now, he's all for it. He made a case on Friday for Khris Davis to participate in the competition, should Davis be chosen.
"A lot of the baseball world doesn't know [as much] about Khris Davis as they should," Melvins said. "I think he would be one of the more entertaining guys."
Davis, who has never taken part in a Home Run Derby, is tied for fifth in the Majors with 20 home runs. He would be the A's first participant in the Derby since Yoenis Cespedes in 2014. But don't expect Melvin to be dragged into pitching to his slugger, despite Davis' request.
"Cespedes said the same thing and I didn't go, and [former A's third base coach] Mike Gallego became a superstar batting practice pitcher because of it," Melvin said. "So we've got plenty of guys who could handle that if that is the case."
Eric He is a reporter for MLB.com based in Oakland.