John Buck belted a sixth-inning grand slam and the visiting Florida Marlins held on to win the opener of an abbreviated two-game series with the major league-leading Philadelphia Phillies, 6-5, on Friday.

Logan Morrison and Greg Dobbs drove in runs for the Marlins, who roughed up Roy Oswalt (6-8) and beat the Phillies for just the fourth time in 13 meetings this season.

Ryan Howard hit a three-run homer for the Phillies, who have lost two straight for the first time since July 27-28.

Buck gave Florida a 6-1 lead by drilling a 1-0 breaking ball just over the scoreboard in right for his second grand slam of the season and fourth of his career.

The Phillies were stymied by Clay Hensley (2-5) for 5 2/3 innings, but after he left Howard cut the margin to 6-4 with his two-out blast off reliever Mike Dunn – Howard's 27th.

Steve Cishek allowed a one-out RBI double to Michael Martinez in the ninth before earning his third save by retiring Shane Victorino and Placido Polanco.

The teams will wrap up Saturday afternoon. A day-night doubleheader was scheduled to avoid Hurricane Irene, but the nightcap was later canceled. Sunday’s contest has been rescheduled for Sept. 15.