MIAMI - Tennis world No 1 Roger Federer was sent crashing out of the Sony Ericsson Open on Tuesday, dropping a 6-4 6-7(3-7) 7-6(8-6) fourth-round marathon match to Czech Tomas Berdych.

MIAMI - Tennis world No 1 Roger Federer was sent crashing out of the Sony Ericsson Open on Tuesday, dropping a 6-4 6-7(3-7) 7-6(8-6) fourth-round marathon match to Czech Tomas Berdych.

The reigning Australian Open champion suffered just his second loss to Berdych in 10 career meetings.

Berdych, the 16th seed, hammered six aces and won 67percent of his first service points in the two hour, 51 minute match on the hardcourts at Crandon Park.

Six-time Grand Slam champ Rafael Nadal and American Andy Roddick were two of eight seeded players to advance to the quarterfinals on Tuesday.

Nadal, who is playing in just his fourth tournament of the season, outlasted fellow Spaniard David Ferrer 7-6(7-5) 6-4.

"With each round it gets more difficult," Nadal said. "I had my moments today but I also had moments where I made more mistakes than usual but it was an important win."

Federer, who has 16 Grand Slam titles, was also knocked out in the third round of his last tournament two weeks ago at Indian Wells and had to withdraw from the Dubai event last month with a lung infection.

Berdych reached his fifth quarterfinal of the season and now has a 15-7 record for this season. He lost to Nadal in the quarters at Indian Wells and made the semis at Brisbane before being eliminated by Roddick.

Five of the top 10 seeds remain in the draw as the only two unseeded players were eliminated on Tuesday.

Nadal won the first set in a tiebreak then raced out to a 3-0 lead in the second before Ferrer rallied in the one hour, 57 minute match.

Nadal, who is an impressive 15-3 this year, is coming off a semifinal finish and a doubles title at the Indian Wells event two weeks ago.

It was his first tournament since retiring in the quarters of the Aussie Open because of a right knee injury.

Nadal next faces Frenchman Jo-Wilfried Tsonga, against whom he owns a 4-1 lead in their head-to-head series.

But Tsonga recorded an impressive win over Nadal in the 2008 Australian Open semifinals. The winner of the Nadal-Tsonga match will play the winner of the Andy Roddick-Nicolas Almagro quarterfinal.

"He has a big serve and a very good forehand," Nadal said of Tsonga.

"It is going to be a tough match because he is playing well right now."

Former champion Roddick continued his mastery over Benjamin Becker by beating the unseeded German 7-6(6-4) 6-3.

"My serve percentage was down early from where I want it, and kind of started slowly inching its way back up and ended where I wanted it to," Roddick said. "It is nice at love-30 to be able to make some first serves."

The 27-year-old American closed the match out with an ace to win his fourth straight match against Becker with no losses.

Also, in the men's fourth round, American Mardy Fish - who knocked out Andy Murray in the second round - retired with a back injury trailing Mikhail Youzhny 6-1 1-0.

Roland Garros finalist Robin Soderling reached the Miami quarterfinals for the first time with a 6-0, 6-7 (7/3), 6-2 win over Chilean Fernando Gonzalez.

Eighth-seeded Tsonga beat No 12 Juan Carlos Ferrero 6-2 6-2 and Nicolas Almagro eliminated Thomaz Bellucci 6-4, 3-6, 7-6 (7/3).

In women's play, Venus Williams, who is the oldest women's quarterfinalist at 29, beat Agnieszka Radwanska 6-3 6-1 to advance to the semis. - Sapa-AFP