Masahiro Tanaka delivers a pitch against the Boston Red Sox...

Masahiro Tanaka delivers a pitch against the Boston Red Sox in the first inning of a game at Fenway Park on April 22, 2014. Credit: Getty Images / Jared Wickerham

BALTIMORE -- No one was calling for an apology, but Masahiro Tanaka gave one anyway.

"I want to apologize to the Yankees organization, my teammates and our fans for not being able to help during this time," Tanaka said Friday afternoon in a statement, his first public comments since being placed on the disabled list with a small tear in his right ulnar collateral ligament Wednesday. "I accept this injury as a challenge, but I promise to do everything I can to overcome this setback and return to the mound as soon as possible."

The Yankees hope that will be in a little more than six weeks, though that might be optimistic.

Tanaka, who complained of elbow discomfort after Tuesday night's loss in Cleveland, was evaluated in Seattle by three top orthopedic surgeons, including Christopher Ahmad, the team physician. The trio agreed it would be best to put off Tommy John surgery, instead prescribing a rehab program that will start Monday with a PRP (platelet-rich plasma) injection.

The possible consequence of that, of course, is if there's little improvement and surgery is deemed necessary, Tanaka will miss most of 2015, as well.

"I give everything I have every time I take the ball," said Tanaka (12-4, 2.51 ERA), who has carried a battered rotation all season. "With that, I also know that there will always be a risk of injury when playing this game that I love. Right now, I feel that the most important thing for me is to keep my head up, remain focused on the task at hand and devote all my energy into healing the injury in order to come back strong."

Also Friday , the Yankees acquired lefthander Jeff Francis from the A's for a player to be named and cash.

Francis, 33, had a 5.89 ERA in 10 appearances (one start) for the Reds and A's this season. A starter most of his career, he is 70-80 with a 4.95 ERA. Because he's mostly relieved this season, there are no immediate plans to put him in the rotation, manager Joe Girardi said.

The Yankees designated righthanded reliever Jim Miller for assignment and recalled Garden City's Matt Daley, another righty reliever.

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