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MIAMI - The Sony Ericsson Open lost its two top seeds in contrasting upsets when Roger Federer and Maria Sharapova were bundled out in the fourth round of the Masters Series tennis event today.
Federer, twice a winner in Miami, will get an early start to his claycourt
preparations following a shock 7-6, 2-6, 7-6 defeat by Guillermo Canas.
It was the second successive tournament the energetic Argentine has beaten the world No 1 after ending Federer's career-best 41-match winning streak a fortnight ago in Indian Wells.
"I was really expecting to win, it was one of those matches I shouldn't have lost," Federer said.
"But he's a great competitor."
Back on the ATP Tour after serving a 15-month doping ban, Canas battled Federer for two hours 38 minutes in a riveting Stadium court duel.
In sharp contrast to that marathon, Serena Williams needed just 58min to humble Sharapova 6-1, 6-1, avenging her sister Venus' loss to the lanky Russian in the third round.
Sharapova's exit left second seed and world No 1 Justine Henin as the top remaining player on the women's side after the Belgian secured a 7-6 7-6 win over Nadia Petrova sealed when the Russia's challenge on match point was ruled out.
The target of racial abuse by a heckler yesterday, Williams heard only cheers as she polished off her opponent with a forehand winner, raising her hand and shouting "number one" as she skipped to the net to shake hands.
Despite playing a limited number of tournaments, Williams' ruthless display sparked talk that the American may again be ready to return to the top of the rankings after years battling injuries and personal problems.
Following her second emphatic win over Sharapova in two months, Williams believes she may have earned back some respect and admitted she would like to stamp her authority on women's tennis in the same way as Federer had on the men's game.
"I think a lot of people might have thought it was a one-off," Williams said.
"I don't know anyone who's won eight Grand Slams and had so many doubters.
"Roger Federer has done an unbelievable job with not only being number one but staying there and just being the best."
Canas remained at a loss to explain his success against the Swiss player who has been almost unbeatable since 2004, compiling a 261-16 record, including 35 titles.
The Argentine, however, has a solid tennis pedigree of his own, having been a top-10 player with six career titles before being suspended.
"I don't know what is the key to beat him, I fight for every point and I think for that I beat him," Canas said.
"I think I played great tennis today, for me it's like a dream."
Second seed Rafael Nadal, of Spain, and third seeded American Andy Roddick made smooth progress into the final eight.
Nadal swept past Argentine Juan Martin Del Porto 6-0, 6-4 and Roddick advanced with a 7-5, 6-3 win over Spain's David Ferrer.
- REUTERS