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Veteran righty Erik Bedard aims for a second straight gem against the Chicago Cubs tonight when his Pittsburgh Pirates host them to open a three-game series at PNC Park.

A 33-year-old Canadian, Bedard tossed six innings of scoreless ball against Chicago when he last faced the Cubs on May 27, allowing two hits and striking out three in a 10-4 Pirates win.

It's his lone start against them in 186 major-league appearances since being drafted in 1999 by the Baltimore Orioles.

Bedard has won just twice in six decisions since that victory but one of the victories came in his last start, when he lasted 6 2/3 innings and allowed one earned run in a 6-2 defeat of Colorado.

The win was his fifth of the season in his 18th start, equaling the total he had while splitting time between Seattle and Boston last season while pitching in 24 games.

Pittsburgh enters the series on a season-high five-game win streak after completing a series sweep on Sunday against the Miami Marlins with a 3-0 triumph.

Starter Jeff Karstens (3-2) scattered five hits and fanned three while walking two to earn the victory. Jared Hughes worked a perfect eighth and Joel Hanrahan notched his 28th save of the season with a clean ninth inning.

"I was just trying to make them take unorthodox, really bad swings," Karstens said. "That's all I'm trying to do. I'm not trying to blow fastballs by people, just keep them off balance."

Pedro Alvarez clubbed a two-run home run and Andrew McCutchen, whose major- league best batting average now stands at .372, went 2-for-4 with an RBI single for the Bucs, who trail Cincinnati by a half-game in the National League's Central Division.

The Cubs counter with righty Jeff Samardzija, who's still trying to recapture the early-season momentum that saw him win five of his initial eight decisions.

The former Notre Dame football player is just 1-5 in eight starts since late May and got a tough-luck no-decision in his last outing after allowing a run on six hits in five innings of Chicago's 5-1 win over Miami on July 18.

His lone victory since May came July 2 in Atlanta, when he allowed a run on four hits in seven innings of a 4-1 triumph.

This is his first start against Pittsburgh after 11 relief appearances, in which he's posted a 1.29 earned run average in 14 innings.

On Sunday in St. Louis, Jon Jay and Tony Cruz hit consecutive two-run doubles in the first inning, backing six scoreless frames from Lance Lynn, and the Cardinals downed the Cubs, 7-0, to complete a three-game sweep.

Travis Wood (4-5) went six innings in the setback, allowing seven runs - six earned - on nine hits with two walks and four strikeouts. Bryan LaHair went 2- for-4 and Starlin Castro added a double.

The Cubs, who had won six of seven prior to this series, were shut out for the second straight game and managed just one run in the set.

They placed a runner on second base in each of the first three innings on Sunday and, for the series, went a combined 0-for-13 with runners in scoring position.

The Pirates swept a three-game series between the teams in Pittsburgh in late May, outscoring the Cubs, 14-6.

The teams split 16 games last season and Chicago last won the season series in 2009.