The four-time All-Star was placed on the 15-day disabled list July 1, his second stint on the DL this season. He hit .207 with seven homers and 30 RBI in 59 games this year.
"Of course, we'd like to have Jim Thome having a Jim Thome year. But at the same time, I want him to get well," Philadelphia manager Charlie Manuel said. "I want him to get healthy. I want him where he's 100 percent and swinging the bat good again."
Thome played for Class-A Clearwater on Tuesday as part of his minor-league rehabilitation assignment. He went 4-for-9 with a home run in four games as the designated hitter for Clearwater, but the Phillies announced Wednesday that the slugger is expected to miss the rest of the season.
Dr. Michael Ciccotti, the team's director of medical services, said Thome will consult with Dr. James Andrews on Monday in Birmingham, Ala., and is expected to undergo surgery there the following day to repair a frayed tendon.
Ciccotti said Thome has done everything asked of him in rehab and could exercise and hit without pain.
"Throwing is what puts the most stress on that area. Every time he throws the ball, he feels persistent pain," Ciccotti said during the Phillies' 9-5 victory over the Dodgers.
The doctor said Thome should be able to fully recover.
Thome, who turns 35 on Aug. 17, has 430 homers since making his major-league debut in 1991.
He is due about $12.5 million in 2006 and $14 million in each of the final two seasons of his six-year contract. The Phillies have a club option for 2009, and he has a no-trade clause.
The player called up from the minors to replace Thome on July 1, rookie Ryan Howard, hit a tiebreaking grand slam in the ninth inning Wednesday night. It was Howard's eighth home run, including a game-winning shot against the same pitcher -- Yhency Brazoban -- on July 19 in Philadelphia.
"It's definitely a loss, being without Thome," Phillies
pitcher Brett Myers said. "But the way Ryan Howard's playing right now, I think that we'll be OK."