NEW YORK, Sept 1: While other big names wobbled at the US Open on Saturday, Venus Williams and Andre Agassi stayed rock solid, recording quickfire victories to slice further through the grand slam draw.

Venus smashed German Martina Mueller 6-1 6-2 in just 41 minutes while Agassi battered Ramon Delgado of Paraguay 6-2 6-1 6-2 in 89 minutes.

Their emphatic victories were in stark contrast to the progress of men’s top seed and defending champion Lleyton Hewitt, who needed five nerve-jangling sets to shake off American favourite James Blake.

The Australian eventually prevailed 6-7 6-3 6-4 3-6 6-3 but the match was not without its uncomfortable moments for the world number one.

“I knew it was going to be a bloody tough match out there,” Hewitt said after firing down an ace to seal the win in three hours 34 minutes.

“I went out there with a Davis Cup mentality and just blocked it out.”

Agassi, though, continued his dominant run.

In a rematch of last year’s third-round encounter, also won by Agassi in straight sets, the American kept his opponent off balance and was in control throughout.

The sixth seed will face unseeded compatriot Jan-Michael Gambill after he clattered Argentine 21st seed Gaston Gaudio 6-0 6-2 6-0.

Venus, seeded second this year behind younger sister Serena, stayed on track for a third successive Open crown with a ruthless victory.

While Serena won the French Open in June and deposed Venus at Wimbledon a month later, at least in New York, Venus still rules.

The American has conceded just six games in three matches at Flushing Meadows and is looking in sparkling form. She meets compatriot Chanda Rubin next.

Rubin, seeded 14, finessed her way past U.S. doubles specialist Lisa Raymond with a tight 7-6 6-4 win.

Far less convincing than Venus on a blustery day six were Monica Seles and Kim Clijsters.

Sixth seed Seles was in the wars again as she fought off a spirited challenge by South Korea’s Cho Yoon-Jeong to reach the fourth round 6-1 5-7 6-3.

She next meets ninth seed Martina Hingis.

Hingis, back in action after ankle surgery kept her out of the French Open and Wimbledon, eliminated South African Amanda Coetzer 6-3 6-4.

Seventh seed Clijsters recovered from a nightmare start to oust dynamic Russian Vera Zvonareva 1-6 7-5 6-4.

The Belgian, Hewitt’s girlfriend, was flattened in the opening set by some impressive power hitting and canny court-craft from the Russian.

But she gradually wrestled control from the 17-year-old to book a clash against 10th seed Amelie Mauresmo of France, who beat Switzerland’s Patty Schnyder 6-1 6-4.

In the men’s draw, 22nd seed Marcelo Rios of Chile retired in his third-round match with right knee tendinitis, giving 14th seed Jiri Novak of the Czech Republic an easy passage into round four and a clash with Hewitt.

Wayne Ferreira of South Africa beat Spain’s Tommy Robredo 6-1 6-2 7-5 to set up a meeting with 20th seed Younes El Aynaoui. The Moroccan beat another Spaniard, Fernando Vicente, 6-2 2-6 6-1 6-2.

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