ST. LOUIS (AP) _ The Busch Stadium magic finally wore off for Heathcliff Slocumb.

The St. Louis Cardinals' reliever had allowed only two runs in 49 1-3 innings at Busch before being victimized in a six-run eighth inning that handed the Pittsburgh Pirates a 10-7 win Tuesday night.

After getting the last out in the seventh inning, Slocumb (0-1) failed to retire any of the three batters he faced in the eighth _ and all three scored. He took the failure in stride, considering the ERA at home is still a miniscule 0.89.

``This is a good place to pitch,'' Slocumb said. ``You're feeling pretty good and things are just not going your way. Sometimes you've just got to dig a little bit deeper.''

Mark McGwire shared the blame. He hit his ninth home run, but his throwing error in the eighth allowed the go-ahead run to score.

``You can't grade it on how hard it is,'' McGwire said. ``I made a bad throw and the floodgates opened. It's that simple.''

Wil Cordero and Pat Meares singled and Luis Sojo walked to load the bases, then pinch hitter John Vander Wal greeted Mike Mohler with a two-run single that tied it at 6. Trying for an inning-ending double play, he whirled and floated a high toss to first base that was way out of Mohler's reach.

It was his first error of the season and it allowed Vander Wal to score.

``I was off-balance and made a bad throw,'' McGwire said. ``Hopefully next time I have a play like that I'll make a better throw.''

The Pirates' big inning spoiled a four-homer game by the Cardinals, who set a major-league record with 55 homers in April. McGwire hit his 531st career homer with a man on in the first off Jason Schmidt. Jim Edmonds tied McGwire for the team lead with his ninth off Jose Silva in the seventh for a 5-4 lead and Ray Lankford had two homers.

The Pirates have only 20 homers on the season, but didn't need the long ball. Brian Giles made it 9-6 with a two-run double for his third RBI of the game, and Kevin Young added an RBI double off Mike James.

``I don't think we're a team that's going to be able to rely on the home runs like the Cardinals can,'' Meares said. ``We've got to bunch hits together and we were able to do that.''

Jeff Wallace (1-0) got the last out in the seventh.

The Cardinals got an off-game from rookie Rick Ankiel, who walked five and allowed four runs in six innings. Ankiel, 20, extended his scoreless streak to 16 innings before Sojo and Morris drove in runs in the third.

An error by Young at first base allowed the Cardinals to tie it at 4 in the fifth.

Schmidt, recovering from shoulder inflammation, was on a 75-pitch limit after being activated from the disabled list earlier in the day. In his first start since April 14, he hit that target in four innings, allowing two runs and three hits.

Coming back against the Cardinals wasn't easy.

``There's no slack anywhere,'' Schmidt said. ``You walk one guy and there's another who comes up that's a threat. It's like that all the way through the lineup.''

Notes: The Cardinals are 17-0 when they don't commit an error and 0-9 when they do. ... Lankford had his 13th multihomer game, his first this season. ... McGwire has 95 homers and 204 RBIs in 194 career games at Busch Stadium. Lankford is the Busch career homers leader with 99 in 650 games. He was in an 0-for-12 slide before homering in the seventh. ... Young has four errors after leading major league first baseman with 23 last season. ... In 31 innings, Ankiel has 25 strikeouts and 25 walks. ... Cardinals pitcher Matt Morris, out since elbow surgery in April 1998, worked 3 1-3 innings in his first rehab start for Double-A Arkansas. He allowed one run on two hits with four strikeouts and two walks, throwing 55 pitches. ... Jason Kendall was 0-for-3 with two walks and is in a 1-for-15 slump. ... Schmidt hasn't won since last Sept. 19 against Cincinnati.