New York, Sep 3 (DPA) Roger Federer will bid for a 14th straight win over longtime rival Lleyton Hewitt as both reached the third-round at the US Open.

Top seed Federer had slightly more problems than expected Wednesday against German Simon Greul before winning 6-3, 7-5, 7-5 while Hewitt put down Argentine Juan Chela 6-3, 6-3, 6-4.

Federer beat Hewitt less than a fortnight ago in Cincinnati, Ohio, and last lost to the Aussie in 2003.

The Swiss superstar ended his first night of this edition under the lights with his eighth ace after nearly two hours.

“The first night session is never easy,” Federer said on a night when men proceeded women for the first time in memory. “I knew I was in for a battle. It’s great to be back and get a win.”

He said that playing Hewitt “always means a lot of intensity”.

“We’ve had some incredible battles,” Federer said. “I’m glad we’re both through.”

Third seed Rafael Nadal marked a winning return to Grand Slam play three months after his last match at a major, advancing 6-2, 6-2, 6-3 over Richard Gasquet.

Nadal, who toppled from his number one ranking when Federer won Wimbledon and was then overtaken by Andy Murray, last played at the elite level when he lost to Robin Soderling on May 31 in the French Open fourth round.

For nearly two and a half months, the Spaniard’s main job was resting a pair of knees plagued by tendinitis.

But the 22-year-old showed he’s eager to resume the battle as he ploughed past his good friend Gasquet in little more than 90 minutes. The winner dominated with seven aces and five breaks of serve in the pro forma opening contest.

“I’m practising well, playing with good tactics and a positive attitude,” said Nadal. “That’s the important thing right now. Later I’ll try to get more rhythm and more confidence winning matches.

“I know I am in the right way, so I think if I have the chance to win few more matches and I get the confidence, we will see what happens later.”

Argentine sixth seed Juan Del Potro took an opening win, beating compatriot Juan Monaco 6-3, 6-3, 6-1 while France’s number nine Gilles Simon defeated Daniel Gimeno-Traver of Spain 6-4, 7-6 (7-3), 6-3.

Crowd-pleasers Marat Safin and Fabrice Santoro bid farewell to their careers at the majors with losses, both men set to retire in two months after the Paris Bercy event.

Austrian Jurgen Melzer beat 2000 Open champion Safin 1-6, 6-4, 6-3, 6-4, while ex-Roland Garros holder Juan Carlos Ferrero stopped Santoro 6-4, 6-3, 6-3.

Two-time women’s champion Venus Williams, bothered with a knee injury that she will not discuss, managed a victory against Bethanie Mattek-Sands 6-4, 6-2.

Williams produced her best tennis in New York in 2000 and 2001 before the rise of her sister Serena.

But the 29-year-old still has her fighting spirit and is determined to not let physical problems get the better of her game.

“I don’t talk about my injuries very much. I don’t dwell on them,” Venus said. “I just do my best.”

Seeds Vera Zvonareva (seventh), Victoria Azarenka (eighth) and number 10 Italian Flavia Pennetta joined Williams in the third round.

Canadian Aleksandra Wozniak handed two-time Grand Slam winner Amelie Mauresmo her earliest career defeat at the Open, 6-4, 6-0.

Kim Clijsters took her career comeback another step with an upset of 14th seed Marion Bartoli 5-7, 6-1, 6-2, while Russian Maria Kirilenko put out 12th seed Agnieszka Radwanska 6-4, 2-6, 6-4.