Jeremy Guthrie was on the mound against Anibal Sanchez, who was facing the O's for the first time in his career.
Wes Helms put the Marlins on the board with an RBI single in the second after Cody Ross walked, and Mike Stanton singled to move him to third. Chris Coghlan singled to drive in Stanton, and Hanley followed with a two-run double to put the Marlins up 4-0.
Ty Wigginton picked up right where he left off with the Fish, smacking a double to lead off the bottom of the second. Things got worse for Anibal from there. Adam Jones singled, and Matt Weiters hit a three-run shot to left-center field, to bring the Orioles within a run.
Both pitchers settled down after the second inning, and traded zeroes until the top of the seventh when Guthrie gave up an RBI double to Gaby Sanchez, and Hanley Ramirez singled to drive him in, putting the Fish in the lead, 6-3.
Anibal Sanchez gave up a two singles to put runners on first and second with one out, and his night on the mound ended as Taylor Tankersley came out of the bullpen to record the final out of the inning.
The Marlins added a run in the top of the eighth when Stanton and Helms singled, and Chris Coghlan grounded into a would-be double play, reaching on a throwing error by Scott Moore that allowed Stanton to score, and make it 7-3 in favor of the Fish.
Brian Sanches gave up a run in the bottom of the eighth, but the Marlins would score three more runs in the ninth, when Cody Ross singled with the bases loaded and Wes Helms added an RBI groundout to put the Marlins up 10-4.
Tim Wood pitched an interesting yet scoreless ninth, and the Marlins took game one of the series, and have won 10 of their last 11 games against the Orioles.