Roger Federer of Switzerland hits a return to Marin Cilic of Croatia during the third round match of women's singles at US Open tennis tournament in New York, Sept. 3, 2011. Federer won 3-1. [Xinhua]

Roger Federer met little trouble in moving forward to the fourth round of U.S. Open on Saturday, eliminating Marin Cilic of Croatia 6-3, 4-6, 6-4, 6-2.

"It was a tough match," Federer, the five-time champion, said after the two hour, 40-minute contest. "Coming in I knew it was going to be tricky and I'm happy that I was able to counter his pace and his good play."

Serena Williams, a three-time winner, demonstrated a powerful comeback in dispatching the first real test from fourth-seeded Victoria Azarenka 6-1, 7-6 (5).

The year's U.S. Open tournament would go down in history with a record 14 retirements with seeded players Tomas Berdych and Marcel Granollers becoming the latest on the withdrawal list.

It would reach 18 victims in the tournament including a couple of walkovers, highlighted by the pullout of Venus Williams and sixth-seede Robin Soderling on Wednesday for illness.

Cilic, the 27th seed, had his chances but could convert only two of nine break-point chances against the third-seeded Swiss.

Williams, who missed last year's tournament at the start of an 11-month injury and life-threatening illness lay-off, announced his strong return in a stylish match overpowering Azarenka.

"Definitely his serve keeps him in there all the time," said Cilic. "And today he was, in those crucial moments, finding a way to make the game a little more difficult for me to read what he was going to do."

The Croat double-faulted to give Federer a 5-4 lead in the third set and never recovered. He had just received a time violation by the umpire prior to his costly error.

Federer conceded the timing of the violation took him by surprise.

"These time violations come out of nowhere sometimes and then they'll never come back again," he said.

"If he was really taking too much time it's correct that you warn a guy but then you should just stay tough and also go to point penalty.

"Marin was playing pretty quick, like I was. It was a tough call."

Federer is currently is tied with Jimmy Connors and Pete Sampras for the most U.S. Open titles since the sport turned professional in 1968.