The Pittsburgh Pirates try to stretch their lead atop the National League Central on Wednesday when they continue a five-game series with the St. Louis Cardinals at PNC Park.

Pittsburgh beat the Cardinals for the fifth straight time on Tuesday, as it swept a doubleheader to wrestle control of the division. The Pirates needed 11 innings to eke out a 2-1 win in the first game, but coasted in the nightcap, 6-0, to move 1 1/2 games ahead of St. Louis in the division.

"We don't undervalue any team or look over anybody. We know anybody can be in the middle of this thing if they click," Matheny said. "As far as Pittsburgh goes, it's no surprise to us. I think more people are surprised than we are. We know they're a good team, that they've been a good team."

Pittsburgh, of course, is chasing not only its first postseason appearance since 1992, but also its first winning season since that year.

"We want more," Pirates manager Clint Hurdle said.

There's been no secret behind the Pirates' recent success, as their starting staff has posted a 1.95 ERA over the last 11 games, eight of which have been wins.

Hoping to continue that trend this evening will be lefty Jeff Locke, who has lost two of his last three starts, but hasn't given up more than two runs in his last eight trips to the hill. In 20 starts this season, Locke has given up three runs or less 18 times, including his last 17 outings.

Locke lost in Miami on Friday, as he surrendered a pair of runs and eight hits, but walked six batters in 6 2/3 innings to fall to 9-3 on the season to go along with a 2.15 ERA.

"Kind of sloppy," said Locke, who has given up just three home runs in his last 17 starts. "I felt really good, but just command wasn't there."

Locke beat the Cards earlier in the year, scattering three hits over seven scoreless innings in his only other start against them.

St. Louis, meanwhile, will counter with righty Adam Wainwright, who is 13-6 with a 2.51 ERA. Wainwright lost in Atlanta on Friday, as he allowed four runs (3 earned) and seven hits in seven innings. He also struck out eight and walked a batter.

"Sometimes you just get beat," Wainwright said. "I had some pretty good stuff tonight."

Wainwright has faced the Pirates 19 times (15 starts) and is 8-4 with a 5.20 ERA.

St. Louis, which is just 1-4 in the Steel City this season, has lost a season- high six in a row.