RODDICK OUT

Andy Roddick has withdrawn from the Masters Cup after spraining his right ankle during practice - an injury that he said did not appear to be serious.

Roddick made the announcement Wednesday, hours before he was to play Roger Federer in a Red Group match. He was replaced in the tournament by 26th-ranked Radek Stepanek, the first alternate here.

Stepanek, of the Czech Republic, could qualify for the semifinals but would have to win both of his matches and hope no more than one of the other players in his group finish with two victories.

"I called him this morning at about 10:00 or 10:30 and said, 'You should prepare like you're going to play. I'm probably 50/50 to play tonight, and I'll let you know as soon as I try to warm up," Roddick said.

Federer has defeated Stepanek 7 - 6, 6 -4.