MLB: Washington 8, Baltimore 5

WASHINGTON, May 24 (UPI) -- Adam Dunn's seventh-inning grand slam, his second homer Sunday, lifted the Washington Nationals to an 8-5 win over the Baltimore Orioles.

Dunn's 14th homer erased a 5-4 deficit with one out in the bottom of the seventh and was his first grand slam this season.

He hit a two-run shot in the sixth and his six RBI was a single-game season high.

Will Nieves had two hits and one RBI, while starter Shairon Martis added one RBI for the Nationals, who averted a three-game interleague sweep with their fifth straight Sunday victory against the Orioles.

The winner was reliever Ron Villone (2-0).

Closer Joel Hanrahan earned his fifth save with a 1-2-3 ninth, including two strikeouts.

Baltimore's Adam Jones hit a two-run seventh-inning homer.

Nick Markakis hit a two-run third inning triple and Aubrey Huff added two hits and one RBI for the Orioles, who have dropped five of seven.

The losing pitcher was reliever Chris Ray (0-1).