Federer, Serena, Wozniacki advance at US Open

Roger Federer and Serena Williams, with 29 Grand Slam titles between them, both cruised into the US Open third round on Thursday as the injury-plagued and illness-hit event claimed more victims.

They were joined in the last 32 by women's top seed Caroline Wozniacki and fourth seeded Belarusian Victoria Azarenka who next tackles a rampant Williams who has lost just three games in two matches so far.

Five-time US Open champion Federer eased past Israel's world number 93 Dudi Sela 6-3, 6-2, 6-2 for his 225th win at a major, one more than Andre Agassi and just eight behind Jimmy Connors's all-time mark of 233.

The third seed next faces Croatian 27th seed Marin Cilic who put out 18-year-old Australian Bernard Tomic, the youngest player in the draw, for the loss of just three games.

"Not much trouble on my serve, and from the baseline I also thought I had the upper hand. When it's like that, obviously it's tough for the opponent, but I just think I was superior today," said Federer.

"It was a good match for me in breezy conditions It was a bit tricky early on to find the rhythm. That's why I was happy to get the first break in the first set."

Federer unleashed 31 winners to Sela's 10 in his 77-minute victory, allowing his opponent just eight points on serve.

Triple women's champion Serena Williams took only 49 minutes to dispose of Dutch qualifier Michaella Krajicek 6-0, 6-1 and now tackles Azarenka who defeated Argentina's Gisela Dulko 6-4, 6-3.

Williams boasts a 5-1 career record over Azarenka, including all four of their Grand Slam meetings.

The American, who is seeded 28 after spending most of the last year fighting injury as well as life-threatening blood clots on her lungs, saw off Krajicek with a 10th ace, having unleashed 25 winners to the hapless Dutch girl's five.

The American insisted that she had not been distracted by seeing sister Venus withdraw from the tournament 24 hours earlier after being diagnosed with an auto-immune disorder.

"It really wasn't that difficult, to be honest. She wants me to do the best; she wouldn't want me to suffer. So now, if anything, it should motivate me more," said Williams.

Top-seeded Wozniacki brushed aside Dutchwoman Arantxa Rus 6-2, 6-0 and next tackles Vania King of the United States.

Meanwhile, the number of walkovers and injury-enforced retirements at the tournament climbed to 13.

Czech 23rd seed Radek Stepanek called it quits in the third set against Juan Monaco of Argentina with a shoulder injury.

Former French Open champion Ana Ivanovic reached the third round without hitting a ball when Czech player Petra Cetkovska, who beat the Serb at Wimbledon and was runner-up at New Haven at the weekend, withdrew through injury.

Ex-world number one Juan Carlos Ferrero, the 2003 runner-up, was also keeping the tournament medical staff busy as he twice needed treatment on a blistered hand and foot before causing the biggest shock of the day.

The 31-year-old defeated French seventh seed Gael Monfils 7-6 (7/5), 5-7, 6-7 (5/7), 6-4, 6-4 to reach the third round where he will take on compatriot Marcel Granollers.

Serbian 11th seed Jelena Jankovic also needed on-court treatment on her back before wrapping up a 6-3, 6-4 win over Australia's Jelena Dokic.

Also going through were Italian seventh seed Francesca Schiavone, who beat Croatia's Mirjana Lucic, and German 10th seed Andrea Petkovic who came from a set and 3-0 down to beat China's Zheng Jie 3-6, 6-3, 6-3.

Russia's 2004 champion Svetlana Kuznetsova was untroubled against Britain's Elena Baltacha, winning 6-4, 6-3.

In the men's event, there were wins for US eighth seed Mardy Fish, Czech ninth seed Tomas Berdych and French number 11 Jo-Wilfried Tsonga.

Germany's Tommy Haas who, at 33, is the oldest player left in the men's draw, was also a winner.

Haas, whose ranking has tumbled to 475, is playing in his 14th US Open and he made the third round with a straight sets win over Colombia's Alejandro Falla.