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Miami, FL (SportsNetwork.com) - A.J. Pierzynski hit a two-run homer in the seventh inning and the Atlanta Braves completed a season-opening sweep of the Miami Marlins with a 2-0 win on Wednesday night.

Pierzynski made his Atlanta debut, as did Shelby Miller, who was acquired in the offseason trade that sent outfielder Jason Heyward to St. Louis.

Miller pitched the first five innings for the Braves, limiting the Marlins to four hits. He struck out four and walked two.

"Obviously I wanted to be a little bit more efficient than five innings, but they put together some good at-bats that led to my pitch count to get up," Miller said.

Brandon Cunniff (1-0) tossed 1 2/3 innings in relief to pick up his first major league win. Cunniff, a 26-year-old right-hander, made his big league debut on Tuesday.

Atlanta is off to its first 3-0 start since 2007.

Miami's Tom Koehler (0-1) tossed six scoreless innings before giving up the blast to Pierzynski.

Freddie Freeman led off the seventh with a single and Pierzynski followed with a drive to right-center field, ending Koehler's outing.

Jim Johnson pitched around a two-out single by Miami's Michael Morse in the eighth before Jason Grilli tossed a 1-2-3 ninth to earn his second save.

"It's disappointing, no doubt," Marlins manager Mike Redmond said about his club's start. "I thought we had a really good spring and to come in and get swept is definitely a big blow."

Miller ran into trouble in the third, as a pair of infield hits and a walk to Giancarlo Stanton loaded the bases with two outs. However, he escaped the jam by getting Morse to ground into a fielder's choice.

Stanton made a spectacular diving catch in right field to rob Freeman in the fourth. He then got up and threw to first to complete a double play.

Game Notes

Koehler allowed five hits, walked three and struck out four ... The Marlins scored only three runs in the series.