LOS ANGELES -- The three game-series against the Washington Nationals that starts Monday stands out starkly on the Los Angeles Dodgers' September schedule.Aside from that and the six games against the second-place San Francisco Giants, the Dodgers play nothing but sub-.500 teams this month.So, in a way the Nationals are a squad to be endured. But to Dodgers manager Don Mattingly, it's also a welcome opportunity: The teams certainly could meet again in October.