Skipper has Nats work on walk-off celebrations

WEST PALM BEACH, Fla. -- Bryce Harper pantomimed a swing, flipped his imaginary bat, pointed to where the home dugout would be and trotted around the bases while the 100 or so Washington fans surrounding the practice field roared.

Spring training is a time for practicing the little things. On Saturday in Nationals camp, that meant rehearsing walk-off home runs.

"It's going to happen," first-year manager Dave Martinez told the players. "One of you guys are going to hit a walk-off home run."

Washington position players began their day with baserunning drills on one of the Nationals' back fields. Before heading to an adjacent field for batting practice, each position player had a chance to…