"Joba Chamberlain is on the disabled list with rotator cuff tendinitis in the right shoulder, and nobody knows if the Yankees' best pitcher will work again this season.

And if Chamberlain does return, could he be sent back to the bullpen to reduce the stress on the hinge?

Tendinitis was diagnosed by Dr. Stuart Hershon and Dr. James Andrews yesterday after Chamberlain was examined in Pensacola, Fla., a day after Hershon, the Yankees' team doctor, stuffed Chamberlain into the Carl Pavano Memorial MRI tube in New York.

Chamberlain has been told to rest for about a week and start a throwing program shortly after the seven-day period expirers. He will be evaluated throughout the process and likely be treated with anti-inflammatory medicine. Chamberlain, who left a start Monday night at Rangers Ballpark, was expected to fly back to New York and not rejoin the Yankees on the current road trip that moves from Texas to Anaheim and Minnesota.

"When he gets back, I am not exactly sure," Joe Girardi said following a 5-3 win over the Rangers last night. "We are not going to rush anything. It's a good diagnosis. Tendinitis is something you will find in 75 percent of the players out there."

Girardi believes Chamberlain's season isn't kaput, but Chamberlain was placed on the DL yesterday. And if there is a miniscule chance of Chamberlain suffering further damage, the future of the franchise likely will be shut down for the season. He is 4-3 with a 2.63 ERA in 32 games (12 starts). Possible complications from rotator cuff tendinitis include a full tear, which would require surgery, bursitis and the treatment failing to improve the discomfort.

If it's anything like the tendinitis that invaded Darrell Rasner's right shoulder in 2006, Chamberlain's season is over.

"I had it in late May and I didn't come back until late August," Rasner said. "But I wasn't throwing like he did the other night."

Right-handed reliever Chris Britton was elevated from Scranton/Wilkes-Barre (Triple-A) to take Chamberlain's roster spot.

Tuesday the Yankees planned to start Dan Giese tomorrow in Anaheim against the Angels and promote Ian Kennedy from SWB to start Saturday. Wanting Giese available in the bullpen last night, Girardi switched the right-handers. Kennedy will start tomorrow night and Giese goes Saturday against the best team in baseball.

Having lost Phil Hughes, Chien-Ming Wang, Jorge Posada, Kennedy and Chamberlain to the DL, the Yankees' postseason hopes are circling the drain. They are 6½ games behind the AL East-leading Rays and trail the wild card-leading Red Sox by 31/2. "