The New York Yankees are used to big crowds, used to so-called "playoff atmospheres" in the regular season. The clubhouse is stocked with players who know what it's like to be in first place. Those are relatively new sensations for the on-the-rise Washington Nationals, who received a lesson or two in the Yankees' first trip to the nation's capital in six years. New York swept the series between division leaders, capping the three-game set Sunday with another solid performance from starter Ivan Nova in a 4-1 win.