Updated

Jeff Karstens tossed seven scoreless innings on Sunday as the Pittsburgh Pirates completed a three-game sweep of the Miami Marlins with a 3-0 victory at PNC Park.

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 have won a season-high five straight.

Anibal Sanchez (5-7) was tagged with the loss after allowing three runs on seven hits with eight strikeouts and no walks over seven innings. Jose Reyes and Logan Morrison each had a hit in the Marlins' fifth straight loss.

After escaping a bases-loaded jam in the top of the first, the Bucs plated the first run of the game in the home half of the frame. Alex Presley began the inning with a base hit and stole second before McCutchen brought him home with a single up the middle.

After the first inning, Miami did not threaten again until the seventh when Morrison led off the inning with a single and Greg Dobbs ripped a sinking liner to left. It appeared that Presley had made the catch, but the ball tumbled out of his glove, giving the Marlins two men on base with one out.

But Karstens remained on his game and needed only one pitch to induce Omar Infante into an inning-ending 5-4-3 double play to keep the lead intact.

The Bucs widened the margin to 3-0 in the home seventh as Casey McGehee began the frame with a double into the right field corner. Alvarez came up next and connected with a fastball down in the zone from Sanchez and watched it sail into the seats in right-center for his 21st homer of the season.

"We need to just get better at-bats and keep fighting, that's all you can do," Marlins manager Ozzie Guillen said. "Every day is going to be tougher and tougher for us."

Game Notes

The Pirates picked up their fourth series sweep of the season. They have also swept the Cubs, Astros, and Royals...Pittsburgh improved to 43-1 when leading after six innings and 47-0 when leading after seven...It was McCutchen's 35th multi-hit game of the season...Pirates second baseman Neil Walker had his 11- game home hitting streak snapped...The Pirates have hit at least one home run in 22 of their last 25 games...Pittsburgh will begin a stretch of 13 consecutive games against NL Central competition on Monday against the Cubs, while Miami will host the Atlanta Braves on Monday...The Bucs improved to a major-league best 32-14 at home.