OUCH: LHP Danny Jackson says his torn rotator cuff could not have come at a worse time.

Jackson will be out at least three weeks and possibly for the rest of the season, after medical tests found a slight tear in the muscles of his throwing shoulder. The Reds put him on the 15-day disabled list and recalled reliever Tim Birtsas from Class AAA Nashville.

Jackson had won his last three decisions and said, "It comes at a very bad time for the team. I was on a roll, pitching very well."

Jackson, who had shoulder surgery in July, couldn't get his shoulder loosened up and skipped a start Tuesday against Montreal. Tests Wednesday revealed the tear. He will get treatment for two weeks, then have the shoulder examined again by team physician Michael Lawhon.

MOVES: The Pirates assigned RHP Jay Tibbs and C Dann Bilardello to AAA Buffalo. Tibbs was 1-0 with a 2.57 ERA in five appearances with the Pirates. He was acquired June 25 from the Baltimore Orioles for a player to be named later.

Meanwhile, RHP Walt Terrell refused to report to Buffalo, meaning the Pirates must either trade him or release him by Monday. The Pirates assigned Terrell to Buffalo Saturday, saying they were prepared to swallow his $3.6 million contract if necessary. . . .

RHP Mike Norris, released by the Athletics this week, cleared waivers and became a free agent. He was 1-0 with a 3.00 ERA in 14 relief appearances for the A's. . . .

The Astros activated 2B Bill Doran from the 15-day DL. Doran had been placed on DL after fracturing his left big toe in Los Angeles on June 19. Doran was batting .264 with one homer, 20 RBI and 12 stolen bases. To make room for Doran, Houston optioned OF Eric Anthony to AAA Tuscon. . . . The Padres purchased the contract of RHP John Davis from AAA Las Vegas and placed RHP Mike Dunne on 21-day DL with a fractured right leg. . . .

The Twins activated RF-DH Randy Bush from the 15-day DL and optioned 1B-DH Paul Sorrento to AAA Portland. . . . The Tigers placed RHP Lance McCullers on the 21-day DL and purchased the contract of RHP Mike Schwabe from AAA Toledo. . . .

Bo Jackson may be put on the DL after medical tests indicated some minor tissue damage in his left shoulder, the Royals said. He was injured Tuesday night while diving for a ball in center field in a game in New York.

TAKING A LOOK: Add Gene Tenace, the Blue Jays' hitting coach, to the list of candidates for the Cardinals' managing job.

Tenace told the Hamilton (Ontario) Spectator that he has been given permission by Blue Jays Manager Cito Gaston and Vice President Pat Gillick to talk with Cardinals GM Dal Maxvill.

"They both told me to go for it," Tenace said.