RHP Ben Sheets was placed on the 15-day disabled list by the Milwaukee Brewers yesterday with a torn back muscle and might miss the rest of the season.

Sheets (10-9, 3.33 ERA) left Friday's game against Atlanta in the eighth inning with what the Brewers said was a strained upper back. He awoke yesterday with discomfort and had an MRI exam, which revealed a tear of a muscle in the upper back that moves the shoulder.

Brewers team physician William Raasch said the injury typically requires four weeks to two months to heal.

"There's a lot of swelling," Raasch said. "We can't tell you how quickly he'll heal. Best-case scenario is 15 days, if he's feeling great. Worst case, two months."

Sheets had a 0-2 count on Chipper Jones with two outs in the eighth inning Friday when he bounced a pitch behind the batter. Sheets said he felt pain on the previous pitch, a curveball to Jones.

Milwaukee recalled RHP Justin Lehr, who was optioned to Class AAA Nashville on Friday.

* TRADE: The San Francisco Giants traded OF Michael Tucker to the Philadelphia Phillies for minor league RHP Kelvin Pichardo.

Tucker, whose playing time has been limited this season after starting in right field for most of 2004, joins a Phillies team in the heart of the playoff chase.

"Right now I don't think a whole lot takes me by surprise," said Tucker, who found out about the deal within minutes of the Giants' 2-1 win over the New York Mets. "It's nice always to be playing for something.

"It's one of those things that comes up and you have no control over it. You do the best you can. They're a good team and it's one of those things you hope they can keep winning."

San Francisco wants to evaluate its young players in the final month of the season. Manager Felipe Alou plans to consistently use Todd Linden and Jason Ellison, who will be recalled from Class AAA Fresno tomorrow to take Tucker's roster spot.

-- From News Services

Brewers' pitcher Ben Sheets goes on the disabled list after tearing a back muscle in Friday's 3-1 victory over the Braves.