The Marlins, who'll move into a baseball-only stadium in 2012 with soon-to-be new manager Ozzie Guillen, won game two of the series on Tuesday when Bryan Petersen crushed the game-winning solo home in the bottom of the ninth inning of a 3-2 triumph.
Doug Slaten (0-2) got the first two outs of the inning with ease, as he struck out Logan Morrison and got John Buck to fly out to deep center, but he left a fastball up and over the plate to Petersen, who deposited it seven rows deep in right field for the walk-off winner.
Javier Vazquez (13-11) was brilliant on the mound. He pitched a complete game five-hitter while striking out nine without issuing a walk. The veteran right- hander won his last six starts.
Vazquez struggled in his first 14 starts of the season, going just 3-7 while holding the highest ERA among qualifying starting pitchers at 6.85. But he turned it around in his final 18 starts, going 10-4 to close out the season. The Marlins went 7-0 in his final seven outings.
Emilio Bonifacio had two hits, an RBI and a run scored for the Marlins, who snapped a four-game skid.
Michael Morse smoked a solo home run and Ian Desmond chipped in with an RBI single for the Nationals, who had their three-game winning streak snapped and missed out on having a chance to finish above .500 on the season for the first time since 2003 (83-79) when the club was still based in Montreal.
Strasburg, who won five of eight decisions last season before an elbow injury that required Tommy John surgery, returned in 2011 with five shutout innings in a no-decision against the Los Angeles Dodgers on Sept. 6.
Two more no-decisions followed before Strasburg dropped a 7-4 verdict against Atlanta on Sept. 23.
In 18 innings across four starts, he's allowed 14 hits and four earned runs with no walks and 14 strikeouts.
He pitched six innings of four-hit, one-run ball against the Marlins in start No. 3 of September and is 1-1 in three career starts against Florida with a 3.86 earned run average.
For the Marlins, 25-year-old right-hander Chris Volstad tries to snap a 10- appearance winless skid.
The Palm Beach Gardens, Fla. native is 0-4 in those 10 starts while trimming his ERA from 5.40 to 4.96 since July 10.
The last victory came against Houston, when he allowed seven hits and three runs in six innings of a 5-4 triumph.
He got a no-decision against the Nationals on Sept. 17 in Washington and is 5-2 in 13 career starts against Washington.
The Marlins have won 11 of 17 over the Nationals this year.