Athletics 9, Nationals 1: Derek Norris hit a pair of three-run homers and Scott Kazmir threw seven scoreless innings as Oakland swept its three-game series against visiting Washington.

Norris hit both homers on 3-0 pitches by Gio Gonzalez, who was traded from Oakland to Washington before the 2012 season in a deal that included Norris. Kazmir (5-1) bounced back from his only loss in his last start, allowing four hits without walking a batter and striking out four.

Gonzalez (3-3) had his shortest outing of the season, lasting 4 1/3 innings in which he gave up seven runs and nine hits. The Nationals scored four runs in 28 innings of the series.

Gonzalez recorded the first two outs in the opening inning but then got into trouble, walking Josh Donaldson and giving up an infield single by Yoenis Cespedes before Norris clubbed his first shot over the fence in left field for a 3-0 lead. The Athletics weren’t finished in the frame, as Alberto Callaspo, Brandon Moss and Nick Punto came back with three straight singles to plate another run.

Craig Gentry led off the second with a single and, two outs later, Cespedes walked before Norris hit another blast over the wall in left for a 7-0 advantage. Moss finished with three hits and Punto drove in three runs for the Athletics.

GAME NOTEBOOK: The last player for the Athletics to homer on a 3-0 pitch was Josh Willingham in 2011. … Oakland leads the majors with five wins when trailing after seven innings. … The Nationals had more errors (five) than runs during the series.