David Robertson #30 of the New York Yankees delivers a...

David Robertson #30 of the New York Yankees delivers a pitch in the fifth inning against the Los Angeles Angels of Anaheim. (April 15, 2010) Credit: Getty Images

David Robertson played catch before last night's game, a good sign for his sore back, and said he'll be ready to relieve Friday night.

The Yankees still figure to play it cautiously with him the rest of the regular season, though general manager Brian Cashman said the injury is a "low-level concern." He added, "It's just a timing issue."

Robertson said his back "locked up" after Monday's outing, and the Yankees sent him for a precautionary MRI Wednesday. Joe Girardi said the exam showed "muscular" damage that will "go away" and that there is nothing structurally wrong.

"My arm feels good, my back feels good," Robertson said after playing catch. "I knew it wasn't anything serious. I wasn't really worried about it."

Royce rolls

Cashman said lefthanded reliever Royce Ring, who pitched well in his 12/3-inning Yankees debut Wednesday night, isn't out of the mix for a postseason roster spot. Ring could give the Yankees a second bullpen lefty to go with Boone Logan.

"You never know," Cashman said. "I'm not going to count anything out. He got guys out at Triple-A all year from the left side. [Wednesday] night was nice to see."

Cashman said "we've had discussions" on how the rotation might be juggled next week to line up pitchers for the Division Series, but he did not get into specifics.

Limiting Hughes

Phil Hughes, with a regular-season innings limit believed to be about 175, is at 1691/3. Cashman said "there's a plan in place" with Hughes the rest of the way but didn't elaborate.

There will be no limitations in the playoffs. Said Cashman, "It's all hands on deck when the postseason starts."

Twins in mix

The Twins - who were idle last night and face the Tigers, Royals and Blue Jays to finish the season - entered last night tied with the Yankees for the best record in baseball at 92-60. As Cashman has said about winning the division title, home-field advantage is important but not the No. 1 priority to him. Team health is.

"I want to win the division, I want to have the best record in the game," Cashman said. "But quite simply, if we have to [rest] some people while we try and do that, I think that's the right way to go."

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