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Albert Pujols certainly looked locked in when he blasted a mammoth homer to turn in the tide in yesterday's victory. That could be bad news for Pirates starter James McDonald, who has struggled to keep the ball in the park as of late.

After getting no help from Pittsburgh over the weekend, the St. Louis Cardinals will try to create their own luck in the National League Central race this evening with the opener of a three-game set against the Bucs at PNC Park.

The Cardinals took two of three from the Rockies over the weekend, but still fell a game off the pace in the division because the first-place Brewers swept their three-game set with the Pirates. That leaves St. Louis five games back with just one series remaining this year against Milwaukee; Aug. 30-Sept. 1 on the road.

Pujols helped his club secure a split of its six-game homestand with a monster two-run homer in the first inning that traveled an estimated 465 feet and helped the Cardinals erase an early two-run deficit en route to a 6-2 win. The bomb by Pujols was the longest ever hit at new Busch Stadium.

"That's an Albert home run," said Cardinals manager Tony La Russa of his slugger's 29th homer of the season. "He hit that ball on the line with the underspin, it wasn't one of those fly balls. That ball was really struck perfectly."

Pujols, who has reached 30 homers in each of his previous 10 big-league seasons, has a good chance of reaching that mark tonight given McDonald's recent struggles. The Pirates hurler has gone 0-2 over a three-start winless streak while allowing seven home runs in that span. Two of those came in a 6-0 defeat at San Francisco on Tuesday as the righty yielded three runs over six innings.

"His stuff has gotten better as the season has gone along," Pirates manager Clint Hurdle said. "Tonight he was beating people with his fastball and threw some good curveballs. It just seems when he's making mistakes, he's paying for them."

McDonald, who had posted back-to-back wins before his current skid in which he didn't allow a run, has fallen to 7-6 with a 4.24 earned run average in 23 starts this year, including a 3.08 ERA in 11 outings at home.

The 26-year-old faced the Cardinals for the sixth time in his career, and second as a starter, back on April 5 in his first start of 2011 and did not get a decision. He lasted 4 2/3 innings and allowed two runs as he was walking himself back from a sore left side.

McDonald will be tasked tonight with trying to salvage Pittsburgh's season as the former surprise contenders in the NL Central have fallen 13 games off the pace and seven contests under .500 thanks to losses in 14 of their past 16 games.

The Pirates may have sealed their fate for good this season after getting swept by the Brewers, scoring just three runs in the series and dropping consecutive one-run games. Sunday's defeat came in extra's, with Milwaukee's Nyjer Morgan lifting a sacrifice fly in the bottom of the 10th inning to hand Pittsburgh a 2-1 loss.

Charlie Morton pitched into the eighth inning and left with a lead, but the bullpen couldn't hold it and Pittsburgh fell to 3-36 at Miller Park since 2007.

"Is there something about this place? Apparently," said Morton. "The proof is in the pudding."

Pittsburgh kicks off a 10-game homestand this evening, all against division opponents, and squares off tonight against Jake Westbrook, who is aiming to win for the first time in four starts and is coming off a decent outing on Wednesday versus the Brewers.

The right-hander lasted eight innings in a 5-1 defeat, giving up three runs over his outing. Control was an issue, with Westbrook walking five to go along with six hits allowed.

Westbrook is 9-6 with a 4.74 ERA in 24 starts after taking his second straight losing decision, but is a solid 6-2 with a 3.54 ERA in 12 games as the visiting pitcher this year.

The 33-year-old has yet to face the Pirates this season and is 0-2 against them lifetime with a 5.00 ERA in six games and two starts.

The Pirates and Cardinals have split six meetings so far in 2011.