Due to a hour-plus rain delay, both teams were forced to go to their bullpen early on. Nationals ace Stephen Strasburg (6-9, 2.96 ERA) only lasted 2.0 innings of no-hit baseball.
The opposing pitcher, Henderson Alvarez (2-3, 3.90 ERA) lasted 1.2 innings and gave up an RBI double to Nationals second baseman Stephen Lombardozzi on his last pitch.
Following the rain delay, Washington used five relievers to close out the game, with Drew Storen (4-2,5.47 ERA) garnering the win.
Mason Dunn (3-4, 3.04 ERA) took the loss for the Marlins.
Miami got solo home runs from Giancarlo Stanton and Jeff Mathis.
Jayson Werth contributed a solo shot for the Nationals.
Following an intentional walk to Werth, Ian Desmond knocked in the winning run with an RBI single in the seventh inning.
The win gives the series victory to the Nationals.
Washington will go for the series sweep on Thursday, 7:05 p.m. ET, with Gio Gonzalez (7-6, 3.72 ERA) facing off against Tom Koehler (3-8, 4.45 ERA).
With their next 17 games games against the likes of the Mets, Phillies and Marlins, the Nationals have a prime opportunity to close the seven game gap that stands bewteen them and the final NL wild-card spot.
Final: Nationals 4, Marlins 3.