Federer plays mind game

Roger Federer explained how he took Tommy Robredo apart set by set to score an impressive victory that sent him through to the US Open quarter-finals.

Federer made light work of 14th seed Robredo on America's Labour Day holiday as the world number one set up a last eight meeting with French Open final opponent Robin Soderling.

"I tried to figure him out a little bit, the way he played me," Federer said of a cautious first set.

Five-time defending champion Federer had gone into the fourth round clash at Flushing Meadows with an 8-1 playing record over Spaniard Robredo having won their last eight meetings.

That winning streak was never seriously under threat at Arthur Ashe Stadium as Federer, in their first match since the 2007 French Open, defeated Robredo 7-5, 6-2, 6-2.

It was a measured performance from the world number one, slowly turning the screw before killing off his opponent in clinical fashion.

Federer added: "I thought he really played my backhand a lot. I expected him to open it up sometimes towards my forehand but he didn't."

Federer now faces Sweden's Robin Soderling in the quarter-finals, the third grand slam in succession that the two will have met, including the French Open final.

Fourth seed Novak Djokovic also swept into the quarter-finals with a solid straight sets victory over Radek Stepanek in the night match on Ashe. The victory for Djokovic sets up a last-eight clash with 10th seed Fernando Verdasco of Spain, who had earlier in the day ended American interest in the US Open men's singles draw by knocking out the unseeded John Isner in four sets.