PITTSBURGH — Ildemaro Vargas hit a two-run double off Aroldis Chapman in Washington's four-run ninth inning, and the Nationals beat the Pittsburgh Pirates 8-6 on Saturday night for a doubleheader sweep.
The Nationals won 5-3 in the first game. DJ Herz pitched five hitless innings and fellow rookie Dylan Crews homered.
Washington put together a two-out rally against Chapman (5-5) in the second game. James Wood singled in Drew Millas to get the Nationals within one.
With runners on second and third, Vargas was sent up to hit for Luis García Jr. With the Nationals down to their last strike, Vargas hit a sinking liner into right field that bounced off the glove of a diving Connor Joe.
Vargas scored on Keibert Ruiz's double as Chapman blew his fifth save in 11 chances this season.
''I didn't play in the first game or the second game, but I kept myself prepared and stayed ready,'' Vargas said through a translator. ''I knew the Pirates had several lefties in the bullpen and the opportunity might be there, and I was called upon and I was very happy to get the job done.''
Chapman has been part of a closer-by-committee approach by the Pirates since David Bednar was removed from the role last week.
''He was a big part of our bullpen and has been a big part,'' Pirates manager Derek Shelton said of Chapman, a six-time All-Star. ''We've got to get him to a point where he's right and executing because when he's right, I think we've seen he's been really elite.''