Opponent: St. Louis Cardinals (70-61 before last night).

Site: Busch Stadium, St. Louis.

Times: 8:10 p.m. today, 7:15 p.m. tomorrow and 2:15 p.m. Sunday.

TV, radio: All games on FSN Pittsburgh, KDKA-AM (1020) and Pirates Radio Network.

Starting matchups: LHP Zach Duke (8-12, 5.01) vs. RHP Chris Carpenter (12-6, 2.96), RHP Shawn Chacon (1-2, 7.88) vs. RHP Jeff Weaver (2-3, 5.92) and RHP Ian Snell (12-8, 4.70) vs. RHP Anthony Reyes (4-6, 4.73).

Season series: Cardinals lead, 7-5.

Three things you should know about the Cardinals: 1. Left-hander Mark Mulder, hit hard in two starts since returning from the disabled list, returned to the DL yesterday and might be done for the year because of lingering left shoulder trouble. 2. Center fielder Jim Edmonds continues to sit out with post-concussion syndrome, and the Cardinals have no idea when he'll be able to play again on a regular basis -- if at all. Shortstop David Eckstein also is out because of a sore oblique. 3. Manager Tony La Russa has had it with injury questions. "Human nature says somebody is going to be distracted [by injury inquiries], and we cannot afford to be distracted," he told St. Louis reporters Wednesday. "The race is close. Concentrate on the guys who are playing -- not the guys who are missing."

The Pirates' key to success: The Cardinals, before facing Florida's Dontrelle Willis last night, were 19-30 when a left-hander started against them.

The intangible: Cardinals closer Jason Isringhausen has been inconsistent. His 3.42 earned run average is his highest since 2000 (3.78 with Oakland) and his nine blown saves are his most since 2001 (also nine with Oakland). In 55 1/3 innings, he has yielded 10 home runs.

On deck: Pirates begin a four-game series Monday in Chicago.