PHOENIX -- The mystery of Arizona Diamondbacks closer Brandon Lyon's elbow problem deepened Wednesday when team physician Michael Lee said he couldn't predict when Lyon would be able to return.
Lyon said he was going to take 10 days off, under doctor's orders.
"You come in these last few days thinking there's going to be nothing there, it's just going to be gone away, it's obviously a little bit frustrating," he said. "But when there's something in there, you want to take it and make sure there's no further damage."
Lyon went on the disabled list May 18, retroactive to May 13, with what the team said was a flexor mass strain in his right elbow.
In the last two days, Lyon has had two MRIs.
The second revealed "some changes of the ulnar collateral ligament" in the joint, and Lee wanted a second opinion before deciding on treatment. He said he was leaning toward Los Angeles Angels team orthopedist Lewis Yocum, who has been treating Barry Bonds' right knee, to provide the second review of the workup.
"We don't feel that [Lyon] is ready to go back out at this point in time, and we have to kind of make some decisions based on further interpretation," Lee said.
After another shaky outing by Brian Bruney, who gave up two runs in the ninth inning of a 12-11 win over the San Diego Padres, Arizona manager Bob Melvin said Jose Valverde might figure in the interim-closer equation.
"I haven't been afraid to mix and match and do what I think is the prudent thing," Melvin said. "Now, Valverde is throwing well enough to where that would be a guy I would look at."
Lyon, 25, was leading the NL with 13 saves when he began to experience elbow pain.
The right-hander missed the entire 2004 season after having surgery on the ulnar nerve in his elbow, but Lee said the existing problem stemmed from a new injury.
"It's not related to the nerve injury he had before nor the surgical process for the repair of that either," Lee said. "This is a different anatomical region that we're concerned about."
He said irregularities were found "in the mid-portion of the ligament," which generally appears strong and healthy, and stressed that he was taking great care because of Lyon's importance to the team.
"We want to make sure that we do everything to ensure that when he comes back he will come back in full force and without a region predisposing him to further injury," Lee said.