The panache of Rafael Nadal [Images] proved no match for the appetite of an American making up for lost time at the U.S. Open on Saturday.

Wildcard James Blake ousted the 19-year-old Spanish second seed 6-4, 4-6, 6-3, 6-1 in the third round to spring another super-sized upset in the men's singles following the first round exit of U.S. fourth seed Andy Roddick [Images].

Another American to go through was Robby Ginepri, who came through a tough five-setter against Germany's [Images] Tommy Haas.

The 19-year-old beat Haas 7-5, 6-7 (3), 6-4, 2-6, 6-3.

The rowdy home fans had even more to cheer when 35-year-old seventh seed Andre Agassi [Images] recovered from a slow start to beat another 19-year-old, Czech Tomas Berdych, 3-6, 6-1, 6-4 7-6.

Agassi and Blake, who is 25 and ranked 49, are potential quarter-final opponents.

"I'm waiting for the alarm clock to go off and I'm going to wake up," Blake gasped before a jubilant Arthur Ashe Court crowd.

"I can't believe how well things are going. This is a dream come true."

The American was ranked only 210 in April after a dreadful 2004 during which he broke his neck, contracted shingles and lost his father to cancer.

He flayed winners left, right and centre on Saturday and by the end French Open champion Nadal cut a forlorn figure, his trademark white bandana, pirate pants and grapefruit-sized biceps mere accessories to defeat.

The humbled Spaniard said simply: "I played bad, he played better. I lost a little bit of confidence because he was playing so well."

Berdych knocked world number one Roger Federer [Images] out of the Olympic [Images] tournament last year and Agassi looked to be in trouble when he was swept aside in the first set.

The chirpy Las Vegan responded like a twice former champion but Berdych would not lie down and led 5-3 in the fourth set before subsiding in the tiebreak 7-2.

"The first set was pretty scratchy but each set my quality picked up," said Agassi, who has so far made light of his chronic back problem. "I just hung on and played a good (tie) breaker."

Another of the men's game's teenage talents, French 13th seed Richard Gasquet, outlasted Croatian Ivan Ljubicic 3-6, 7-6, 6-7, 6-3, 6-2.

Gasquet, the 2002 junior champion at Flushing Meadows, is making his debut in the senior draw and the 19-year-old matched his best grand slam performance having also reached the last 16 at Wimbledon [Images] this year.

Women's second seed Lindsay Davenport [Images] brushed aside Spain's Anabel Medina-Garrigues 6-3, 6-2 in the evening session to set up a last-16 meeting with France's [Images] Nathalie Dechy.

French third seed Amelie Mauresmo eased to a 7-5, 6-3 win over Anna-Lena Groenefeld of Germany. However, Justine Henin-Hardenne and Elena Dementieva had to survive plucky fight-backs.

French Open champion Henin-Hardenne, the seventh seed, took the first nine games of her 6-0, 7-6 third round win over South Korean Cho Yoon-jeong.

Cho, though, suddenly came to life and forced a tiebreak with some punishing groundstrokes before Henin-Hardenne restored order, winning it 7-4.

The Belgian will face Mary Pierce, the Frenchwoman she thrashed in the French Open final, in the last 16. Pierce, the 12th seed, advanced after opponent Jelena Jankovic of Serbia and Montenegro quit with a back injury trailing 6-3, 3-0.

Sixth seed Dementieva, who was runner-up last year, flirted with defeat in her 6-1, 4-6, 7-6 victory over fellow Russian battler Anna Chakvetadze [Images].

NO EXCUSE

As usual, Dementieva's game was infested with double-faults -- she served 19 in total. "I have no excuse for serving like that," she admitted.

The Russian plays Swiss 11th seed Patty Schnyder in the fourth round, a repeat of their last 16 clash at the Australian Open [Images] which Dementieva lost having led by a set and 4-1.

Schnyder beat Japan's [Images] Shinobu Asagoe 6-1, 6-3.

The other all-Russian clash in the women's third round was just as bizarre. Anastasia Myskina [Images], the 13th seed, squandered match points before losing 0-6, 6-3, 7-6 to Elena Likhovtseva.

Chile's Olympic champion Nicolas Massu reached a grand slam fourth round for the first time when he thrashed Switzerland's [Images] Stanislas Wawrinka 6-4, 6-3, 6-0.

He will play Argentine eighth seed Guillermo Coria, a four-set winner over Swede Robin Soderling.

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