Roger Federer suffered a stunning 7-6, 2-6, 7-6 defeat by Guillermo Canas in the Sony Ericsson Open fourth round on Tuesday, the world number one's second loss to the Argentine in successive tournaments.

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.

Canas, who snapped Federer's 41-match winning streak at Indian Wells two weeks ago, battled the Swiss defending champion for two hours 38 minutes in a riveting Stadium court duel that ended when the Argentine sealed victory with a service winner.

Back on the ATP Tour after serving a 15-month doping ban, Canas joins select company, becoming just the fifth player to record back-to-back wins over Federer who lost only two hard court matches all last season.

"I really expecting to win, it was one of those matches I shouldn't have lost," Federer told reporters. "But he's a great competitor. He played well both times and I just couldn't put him away."