Washington was the last major league team without a loss.
Xavier Paul had his first career pinch-hit grand slam during a seven-run seventh inning. The Reds had more homers than the Nationals had hits (5).
Dan Haren (0-1) had a rough time in his Nationals debut, giving up four homers and six runs in four innings.
Homer Bailey (1-0) gave up two hits in six scoreless innings. The right-hander hasn't given up a run in his last 19 regular-season innings, a streak that includes his no-hitter in Pittsburgh on Sept. 28.