WASHINGTON -- The Indians have yet to say that Michael Brantley is done for the season, but the clock is ticking and the star left fielder has encountered another setback.

Brantley's season-long comeback, which has hit a series of snags and required consultation with four doctors to date, has stalled once again due to discomfort around his right shoulder. Following a meeting with Dr. Stephen O'Brien on Monday in New York, Brantley has been diagnosed with "chronic biceps tendinitis," and surgery has not been ruled out.

"It's a possibility," said Indians president of baseball operations Chris Antonetti. "How likely and what the exact nature of a surgery would be, that's why we need to get all of the doctors together to figure out what their recommendation would be."

Brantley had been taking part in indoor batting practice for a little more than a week, leading up to his visit with Dr. O'Brien at the Hospital of Special Surgery in New York. Prior to resuming his hitting program, the left fielder had Dr. Jason Genin perform a minor procedure on July 22 in Cleveland to break up scar tissue in the front of his right shoulder.

Earlier this season, Brantley also had consultations with Dr. Keith Meister in Dallas (June 21) and Dr. Craig Morgan in Wilmington, Del. (May 17). Morgan, who did surgery to repair a labral tear in Brantley's right shoulder on Nov. 9, administered an anti-inflammatory injection in the May checkup. Meister, who gave Brantley a cortisone shot in the June meeting, first diagnosed the biceps tendinitis.

Antonetti said the goal now is to have that team of doctors, along with Cleveland's medical staff, determine the next course of action for the sidelined outfielder.

"We're still in the process of gathering information," Antonetti said. "Michael saw Dr. O'Brien yesterday in New York to help us get a little more information. Now, the plan moving forward will be to get the group of doctors that have seen Michael and are familiar with his case, to get together and come up with a plan of care for him. What exactly that means, we don't know yet."

Brantley, 29, played in just 11 games for Cleveland between late April and early May after opening the season on the 15-day disabled list. He returned to the shelf on May 14 and eventually embarked on a Minor League rehab assignment from July 11-17 before experiencing lingering issues around his shoulder.

"He's done such a good job of getting ready to play," Indians manager Terry Francona said. "And then, once he gets to that last step, he feels it. So, we're trying to get to the bottom of it. The most important thing is to get to the bottom of it and, whatever needs to be done, we will. We should know something here pretty soon."

Though the Indians have been able to lead the American League Central for much of the season without their star outfielder, his return was seen as a potential boost to their pennant hopes this fall. Brantley finished third in AL MVP voting and made his first All-Star Game in 2014, and received AL MVP votes again last year after hitting .310 and leading the Major Leagues with 45 doubles.

Whether or not Brantley suits up again this season for the Indians, the team has appreciated how hard Brantley has worked behind the scenes.

"There's nothing more that anyone could've asked from Michael," Antonetti said. "I know he's been disappointed that he hasn't been able to come back and impact the team the way he had envisioned. But, the one thing we all know is it's not for the lack of work, effort, commitment, passion for getting back. There's nobody who has worked harder throughout a rehabilitation process than Michael, nor has been more diligent in doing it."