The Washington Nationals, mounting a drive in the National League East, bolstered their depth by acquiring outfielder Scott Hairston from the Chicago Cubs in a trade for a minor league pitcher, the team said on Monday.

Right-handed hitting Hairston, 33, was batting just .172 but had belted eight home runs with 19 runs batted in over 99 at-bats this season, including a pinch-hit home run in Chicago's 4-3, 11-inning victory against the Pittsburgh Pirates on Sunday.

Washington sent Dominican right-hander Ivan Pineyro to the Cubs. Pineyro, 21, was a combined 6-3 with a 3.24 earned run average over stints with Single-A Hagerstown and Potomac this year.

The Nationals (46-42), who were short on right-handed hitters, have won four straight to move within four games of the NL East leading Atlanta Braves.