The remnants of Hurricane Frances swept into New York to leave the eagerly-awaited U.S. Open quarter-final between top seed Roger Federer and twice former champion Andre Agassi hanging in the balance on Wednesday.

Former champion Lindsay Davenport and ninth-seeded Russian Svetlana Kuznetsova dodged the showers to set up a semi-final clash in the women's singles but the rain returned to interrupt Federer and Agassi with the Swiss player 6-3, 2-6, 7-5 up.

Fifth seed Tim Henman was also on the verge of a first U.S. Open semi-final appearance, leading 22nd seed Dominik Hrbaty of Slovakia 6-1, 7-5, 4-5.

When play finally began on the Arthur Ashe Court, soon after 1945 local time (2345 GMT), Federer and Agassi were greeted by a half-empty stadium.

The predicted electric atmosphere did not take long to materialise though as world number one Federer, looking to become the first man to win three Grand Slam titles in the same year since Swede Mats Wilander in 1988, took the opening set.

But as the stadium filled up, so Agassi, the darling of the New York crowd, lifted his game.

The 34-year-old, champion in 1994 and 1999, began to target the Federer backhand and it paid dividends when the American broke for a 2-0 lead in the second set.

CONSTANT PRESSURE

Under constant pressure from the depth of Agassi's groundstrokes, Federer began to make mistakes as he dropped the set.

Roared on by the crowd, Agassi had a chance in the second game of the third set but Federer saved a break point with an ace and though the veteran American continued to play the better tennis, he was unable to press home his advantage.

Agassi had not faced a single break point in the third set until a double fault at 30-30 in the 11th game handed Federer his opening. A netted backhand from Agassi then gave the Swiss the break and a strong service game helped him take the set.

The two players were level at deuce on the Agassi serve in the opening game of the fourth set when the rain returned.

Henman, looking to become only the second British man to reach the last four at Flushing Meadows in the Open Era, blitzed through the first set and saved a set point at 4-5 in the second before doubling his lead.

The fifth seed, who reached the semi-finals at the French Open and the quarter-finals at Wimbledon earlier this year, broke for 2-1 in the third but Hrbaty levelled at 4-4 and held serve for 5-4 before they were forced off court.

The few fans who ventured on to the Louis Armstrong Court witnessed a demolition job from fifth seed Davenport as she dismissed unseeded Japanese Shinobu Asagoe 6-1, 6-1 in 45 minutes.

VERY EXCITED

"I just really wanted to play today," Davenport told reporters.

"I didn't want to have to come back here tomorrow and possibly go through the same thing. So I was very excited when we walked on the court and it looked like we were going to have some dry time.

"At about 6-1, 5-1, I thought, 'if it rains now, I'm going to die'. Then I started to hurry it up a bit."

Despatched to Court 11 where only a smattering of spectators greeted them, ninth seed Kuznetsova trailed 2-0 against fellow Russian Nadia Petrova, the 14th seed who beat defending champion Justine Henin-Hardenne in round four.

But Kuznetsova hit back to seize the first-set tiebreak and an early break in the second helped her clinch her first Grand Slam semi-final appearance with a 7-6, 6-3 triumph.

"This has been a strange year for me, it's been good but could have been so much better," Kuznetsova said after joining another Russian, Elena Dementieva, in the last four.

"At the French Open I had a match point against (Anastasia) Myskina and didn't take it and she went on to win a Grand Slam.

"Then I had a big disappointment at Wimbledon where I lost in the first round, so this makes up for that."