Federer, Djokovic in rematch

Organisers reschedule finals after player protest; Serena to take on Wozniacki

Playing his first Grand Slam tournament as a 30-year-old, the five-time US Open champion was lethal with his serve, whipped angled winners with swashbuckling aplomb and was razor-sharp at the net.

The third-seeded Federer advanced to a scintillating showdown in the last four against top seed Novak Djokovic for his eighth straight US Open semifinal appearance.

World number one Djokovic, the Australian and Wimbledon champion, reached the semis when his Serbian Davis Cup team-mate Janko Tipsarevic retired with a leg injury while trailing 7-6, 6-7, 6-0, 3-0.

Federer has lost just one set at Flushing Meadows on his way to the semis. “I played great,” said Federer, who boomed in 72 percent of his first serves in Thursday's closing match at Arthur Ashe Stadium. “For me it continues, and that is awesome.

“I'm very happy with the way I'm playing, the way I'm moving and I'm enjoying myself on the court.”

Djokovic carries a remarkable 62-2 season record into the semifinal clash. Federer said he looked forward to their fourth successive reunion in the US Open semifinals.

Djokovic won last year with Federer taking their previous two showdowns at Flushing Meadows.

Rafael Nadal, meanwhile, flexed his muscles with a show of power rarely seen in the modern game. Showing no mercy against his unseeded opponent Luxembourg's Gilles Muller, the Spaniard stormed into the quarterfinals with a ruthless display, then led a player revolt that pressured organisers into rearranging the schedule after the two previous days were washed out by rain.

The defending champion was quick to express his displeasure after weather delays left him facing the daunting prospect of having to win four matches in as many days to retain his title.

"That's not fair, but that's what it is," Nadal growled after trouncing Muller 7-6, 6-1, 6-2 in a little over two hours. “If you don't have rest, you have a big chance not (to) be fit enough to play well (in) the next match.”

Andy Roddick and Andy Murray were also unhappy at the schedule, which they said favoured players in the top half of the draw, who would only have to play three times in four days.

Within hours, the US Tennis Association (USTA) announced they had bowed to the players' demands.

The women's final, originally scheduled for Saturday, was put back a day, while the men's championship decider was shifted from Sunday, the 10th anniversary of the September 11 attacks, to Monday, marking the fourth year in a row the last major of the year has gone into overtime.

"We revised the schedule for the remainder of the 2011 US Open in an effort to be fair to the players and our ticketholders," tournament director Jim Curley said in a statement.
But not all the players were impressed with the decision, including world number one and title favorite, Serbian Djokovic. "I'm not really happy about that, to be honest," he said. The scheduling changes were in stark contrast to events on court, where almost everything went according to the script..

Serena Williams overcame a wobbly start with her serve, in which she was broken in each of her first three games, to defeat Anastasia Pavlyu-chenkova of Russia 7-5, 6-1.
In the semifinals, the American faces world number one Caroline Wozniacki after the Dane beat Germany's Andrea Petkovic 6-1, 7-6.

Australia's Sam Stosur demolished world number two Vera Zvonareva 6-3, 6-3 and will next play unseeded German Angelique Kerber, who upset Italy's Flavia Pennetta 6-4, 4-6, 6-3 in their quarterfinal.

Murray produced his best display of the tournament in beating American wildcard Donald Young 6-2, 6-3, 6-3 but Roddick and John Isner kept the Stars and Stripes fluttering in the men's draw by beating higher-ranked European opponents.

Roddick showed glimpses of the form that saw him win at Flushing Meadows in 2003 as he ousted Spanish fifth seed David Ferrer 6-3, 6-4, 3-6, 6-3 to set up a quarterfinal clash with Nadal. The towering Isner beat French 12th seed Gilles Simon 7-6, 3-6, 7-6, 7-6 in a match unsurprisingly dominated by his serve and advances to face Murray.

Results (prefix denotes seeding): Men: Quarterfinals: 3-Roger Federer (Sui) bt 11-Jo-Wilfried Tsonga (Fra) 6-4, 6-3, 6-3; 1-Novak Djokovic (Ser) bt 20-Janko Tipsarevic (Ser) 7-6 (7-2), 6-7 (3-7), 6-0, 3-0 (retd).

Fourth round: 21-Andy Roddick (US) bt 5-David Ferrer (Esp) 6-3, 6-4, 3-6, 6-3; 28-John Isner (US) bt 12-Gilles Simon (Fra) 7-6 (7-2), 3-6, 7-6 (7-2), 7-6 (7-4); 2-Rafa Nadal (Esp) bt Gilles Muller (Lux) 7-6 (7-1), 6-1, 6-2; 4-Andy Murray (Bri) bt Donald Young (US) 6-2, 6-3, 6-3.

Women: Quarterfinals: Angelique Kerber (Ger) bt 26-Flavia Pennetta (Ita) 6-4, 4-6, 6-3; 1-Caroline Wozniacki (Den) bt 10-Andrea Petkovic (Ger) 6-1, 7-6 (7-5); 28-Serena Williams (US) bt 17-Anastasia Pavlyuchenkova (Rus) 7-5, 6-1.