OAKLAND, Calif. -- Athletics left-hander Dallas Braden received an injection of platelet-rich plasma in his strained, surgically repaired throwing shoulder and will not do any baseball activity for three weeks.
Manager Bob Melvin said Tuesday that Braden received the shot during Monday's examination in New York with Dr. David Altchek, and will be limited to strengthening exercises and rehab until he is cleared to resume his throwing program. Altchek operated on Braden's shoulder last May 17.
Braden had initially hoped to return to the A's revamped rotation by early May before suffering his latest setback last week.
The pitcher stayed in Arizona when Oakland opened the regular season with two games in Tokyo against Seattle. He threw a bullpen session then felt some discomfort the next day while playing catch that caused him to stop his session, Melvin said.
"From what we hear and what the doctor told him, he needed a shot and to lay off," Melvin said before Tuesday night's exhibition game with the San Francisco Giants.
Melvin said he doesn't expect Braden, who threw a perfect game on May 9, 2010, against Tampa Bay, to start from scratch building his strength back up like he did after the surgery.
Braden received a $3.35 million, one-year contract in mid-December. He made three starts last season before being sidelined by a shoulder injury that required the surgery to repair a torn capsule. He was 1-1 with a 3.00 ERA before going on the disabled list April 18.
Fellow left-hander Brett Anderson, meanwhile, made an encouraging step Tuesday in his recovery from reconstructive elbow surgery last July. Anderson, on the 60-day disabled list, threw a 40-pitch bullpen session that included sliders, changeups and curveballs with the catcher standing on the plate. The tentative timeline of August for Anderson's return is still the goal.
"I think he looks as good as he could look," Melvin said. "He looks terrific. His pace is a great pace."
Shortstop Cliff Pennington was held out of Tuesday's lineup as a precaution after he experienced tightness in his left groin a night earlier. Pennington said he felt much better and would be playing if the game counted. He also said there is no reason he won't be ready for Friday's home opener against the Mariners.
"It's sore, but it's sore from treatment," Pennington said.
Also Tuesday, the A's placed first baseman Daric Barton on the 15-day disabled list because of a strained right shoulder that limited him this spring.
The expected move for Barton is retroactive to March 24. He appeared in only seven games this spring, batting .176 with a double and no RBIs. He is eligible to come off the DL during Sunday's off day, meaning he could play as soon as Monday when the A's host the Kansas City Royals.
"We'll see where his progress is at that point," Melvin said. "We just felt like he needed, and he felt like he needed, a few days in a row to get his arm strength."
Oakland, which already played two regular-season games against Seattle last week in Tokyo, has 26 active players on its 40-man roster and must trim one more by Wednesday ahead of Friday's game against the Mariners.
Melvin was still waiting Tuesday for results from an MRI exam on reliever Joey Devine's surgically repaired right elbow. He had Tommy John surgery in April 2009 and is experiencing more problems. Devine is already on the DL with right biceps tendinitis and has been shut down for now.