PITTSBURGH -- It did not take Jordy Mercer long to make an impact with the Pittsburgh Pirates.
Just a few hours after being called up from the minor leagues, the infielder hit a two-run home run to lift the Pirates to a 3-1 victory over the Washington Nationals at PNC Park.
The Pirates (17-12) won for the fourth time in six games and handed the Nationals (15-15) their fourth loss in six games.
Pittsburgh's Andrew McCutchen beat up on Washington once again by going 3-for-4 with a home run. The All-Star center fielder is hitting .456 (41-for-90) with 10 homers and 22 RBIs in 24 career games against the Nationals and also 6-for-6 against Washington left-hander Ross Detwiler.
Starling Marte and Gaby Sanchez added two hits for the Pirates. Marte is 15-for-43 (.349) in his last 10 games.
A.J. Burnett (3-2) was dominant in winning his third straight start, allowing only one run and five hits in seven innings with one walk and nine strikeouts. He has a 1.80 in his last three starts after going 0-2 with a 3.71 ERA in his first three.
Mark Melancon worked a scoreless eighth inning, holding a 3-1 lead by escaping a first-and-third when he struck out Bryce Harper.
Jason Grilli earned his 12th save in as many opportunities.
Detwiler (1-3) gave up three runs in five innings, allowing six hits and two walks while striking out five.
Washington first baseman Adam LaRoche had two hits after going 2-for-38 in his previous 11 games.
Mercer put Pittsburgh ahead 3-1 in the fifth inning with a two-out, two-run home run into the first row of the left-field bleachers. Mercer was recalled when second baseman Neil Walker was placed on the 15-day disabled list with a lacerated right hand.
McCutchen hit his fourth home run of the season with two outs in the second inning to open the scoring.
The Nationals tied it 1-1 in the fourth as slumping Danny Esponisa hit an RBI single to right field. The second baseman had been 1-for-21 in his previous nine games, dropping his batting average to .173. He was benched for the previous two games by manager Davey Johnson
NOTES: Washington activated third baseman Ryan Zimmerman from the 15-day disabled list before the game, and he batted cleanup. Third baseman Anthony Rendon was optioned to Double-A Harrisburg. Zimmerman had been out since April 18 with a strained left hamstring. ... Nationals right fielder Jayson Werth sat out with a strained left hamstring and will likely miss the entire three-game series. Werth returned to the lineup Thursday at Atlanta after missing two games but left in the fifth inning. ... Pittsburgh selected the contract of right-handed reliever Jose Contreras from Indianapolis and optioned right-handed reliever Jared Hughes to the same club. ... Walker is expected to be activated May 12, the first day he is eligible since the move is retroactive to April 27. ... Pirates right-hander Charlie Morton was removed from his rehab start with Indianapolis after three innings on Friday night because of shoulder inflammation and will be reevaluated Saturday in Pittsburgh. Morton is trying to come back from Tommy John elbow reconstruction surgery performed last June. ... Pirates right-hander Jeff Karstens, who has been out all season with right shoulder inflammation, pitched a two-inning simulated game Friday and will likely be sent to extended spring training in Bradenton, Fla., on Sunday or Monday. ... Stephen Strasburg (1-4, 3.13) will start for Washington on Saturday afternoon against left-hander Jeff Locke (3-1, 2.83).