Padres right-hander Erik Johnson -- making his Petco Park debut after being acquired in the James Shields trade -- allowed five runs over six frames, including the three homers.
Wil Myers went deep for the Friars, his 15th of the season, tying him with Matt Kemp for the team lead and giving him eight since the start of June, the most in the Majors. Myers, Kemp, Melvin Upton Jr. and Alexi Amarista had two hits apiece.
MOMENTS THAT MATTERED
Power alley: It began with Harper's first homer in 14 games, as the Nationals continued the power surge that has helped carry their offense, which began the day leading the National League in home runs.