Tigers reliever Troy Percival likely will miss the rest of the season because of a partial muscle tear in his right forearm.

Percival, signed by the Tigers during the offseason to be their closer, went on the disabled list for the second time this season on July 15, a move retroactive to July 10. He was examined Monday by Lewis Yocum, who conducted an MRI exam and said Percival must rest for two months. It is not known if he will need surgery.

"We have some depth, but we've lost a part of that," Tigers Manager Alan Trammell said yesterday. "We're fortunate we still have some pretty good arms."

Mostly because of health issues, Percival, 35, did not perform to expectations. The former all-star was 1-2 with a 5.76 ERA and eight saves in 11 opportunities over 25 innings. He went on the disabled list on May 10 with the same injury, returning to the lineup on June 5 before re-aggravating the injury on July 9.

Percival was given a two-year, $12 million contract by the Tigers. Trammell said he didn't regret the deal because of Percival's veteran presence in the bullpen.

Kyle Farnsworth will take over the closer's role, Trammell said. Farnsworth is 1-1 with a 1.85 ERA and three saves. He could be suspended for his role in a fight Sunday against Kansas City.

* RED SOX MOVES: The Red Sox began to overhaul their roster, acquiring IF Tony Graffanino from the Kansas City Royals and OF Adam Hyzdu from the San Diego Padres.

Boston also designated left-handed reliever Alan Embree for assignment.

The Red Sox, who lost six of seven before beating Tampa Bay last night, sent Class A LHP Juan Cedeno and Class AAA OF Chip Ambres to Kansas City. To make the deal possible, Graffanino waived most of the $400,000 trade bonus called for in his contract, with the Royals making a $100,000 payment instead.

"We hated to lose Graf," Royals Manager Buddy Bell said after Kansas City beat Cleveland last night. "He was a big part of this team and a big part of this clubhouse. The Red Sox are getting a great guy."

The Red Sox sent RHP Scott Cassidy to San Diego for Hyzdu, who joins the Red Sox organization for the fourth time. Former Boston OF Gabe Kapler also was back in the clubhouse yesterday, having re-signed over the weekend after an aborted stint in Japan.

-- From News Services

Tigers closer Troy Percival has a partial muscle tear in his right forearm. The former all-star was 1-2 with a 5.76 ERA and eight saves.