"The tally for Lastings Milledge didn't get any better a day later: another 0 for 4, another deep ball he couldn't run down.

Still trying to master the art of covering center field, Milledge also has struggled mightily as the Washington Nationals' newly minted leadoff man. In the Nationals' first two losses, Milledge has achieved little other than frustration.

"I'm supposed to be the guy who gets things started," Milledge said after Tuesday's 8-3 loss to the Florida Marlins at Dolphin Stadium. "It's not happening now."

Milledge's performance has perplexed Nationals outfield instructor Marquis Grissom, a four-time Gold Glove outfielder who also was among the game's best leadoff men during his 17-year career.

"I don't know if it's the lighting or he's nervous," Grissom said, "or what it is."

In Monday's opener, Milledge couldn't catch up to a ball hit by Emilio Bonifacio that turned into an inside-the-park home run. A day later, Bonifacio smacked a similar ball that Milledge dived for but missed. He ended up with a triple.

"He just needs to practice more," Grissom said. "Practice, practice, practice."

Center field isn't new for Milledge, who moved there last season after playing mostly left and right field for the New York Mets in 2006 and 2007. But Milledge does not look comfortable. "