"He felt good yesterday and felt even better today," A's manager Bob Melvin said Friday. "We're confident enough to have him throw a bullpen tomorrow."
The right-handed Gray is expected to throw several bullpen sessions before the A's determine his next step, which could be a rehab start. That would put him on track to return to the club in mid-June.
"You always have your fingers crossed with a guy like that," Melvin said. "You're hoping that it's a limited amount of time on the DL. The first part of it is making sure he feels good enough to play catch and then the second part is throwing a bullpen. That is good news for us."
Gray is 3-5 with a 6.19 ERA in nine starts this season, after pitching to a 2.88 ERA in his first three seasons with the A's.
• Right-hander Henderson Alvarez, who suffered a setback while rehabbing his surgically repaired shoulder earlier this month, is throwing again. He threw from 90 feet out on Friday and is scheduled to throw from a distance of 105 feet on Saturday. Reliever Liam Hendriks (triceps strain) is on the same throwing program.
• Right-hander R.J. Alvarez, who underwent minor elbow surgery in March, will throw his second bullpen session on Saturday and could soon face hitters.
Jane Lee has covered the A's for MLB.com since 2010.