After evaluating Moylan on Wednesday in his Birmingham, Ala., offices, Dr. James Andrews determined it was too early to determine whether the Australian reliever would need to undergo Tommy John elbow ligament replacement surgery.
But Andrews confirmed the ulna collateral ligament in Moylan's right elbow has been compromised by a bone spur. The Braves' medical staff made this same diagnosis during its evaluation in Atlanta on Monday
Andrews wants Moylan to continue rehabbing over the next two weeks in hopes that the elbow might return to health. But because the spur is affecting the ligament, the Braves aren't able to be too optimistic.
"I think, realistically, we know that it's a long shot that we can get Peter back this season," Braves general manager Frank Wren said. "But we're going to give it two weeks to see what happens."
Whether Moylan undergoes the Tommy John surgical procedure now or in early May, his targeted return for next year would be relatively the same. The rehab process is almost always one full year.
"A couple of weeks either way, it's not going to make a difference," said Braves manager Bobby Cox, who also conceded there's little reason to believe Moylan will be able to return this season.
Moylan felt some discomfort in his elbow early in Spring Training and again while throwing a ninth-inning pitch in Friday night's win over the Nationals. When he awoke on Saturday, he was unable to fully bend his right arm.
Since encountering a rocky season debut last season, Moylan has proven to be one of the Braves' most reliable relievers. In his past 86 appearances dating back to April 18 of last year, he has posted a 1.51 ERA and surrendered just 67 hits in 95 1/3 innings.
"You have to move on and somebody has to pick him up," Cox said.
Unfortunately for the Braves, Moylan's injury came just three days after closer Rafael Soriano was placed on the 15-day disabled list with a strained right elbow. Soriano will attempt to throw a bullpen session this weekend and he could possibly return next week.
As for Mike Gonzalez, who is coming back from Tommy John surgery, the reports have indicated that he's been throwing well in extended Spring Training. Cox indicated Thursday that Gonzalez might be able to return earlier than his original early June timetable.
"We have been actively looking to improve our bullpen and we'll continue to do so," Wren said. "We like the arms that we have out there and there are some good arms [in the Minor Leagues]. But we're always looking at ways to improve."
Mark Bowman is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.