Nadal is looking to end an eight-month title drought

Second seed Rafael Nadal also progressed, with a straight-sets win over Frenchman Arnaud Clement.

Nadal next faces fellow Spaniard Fernando Verdasco, who overcame Italian qualifier Andreas Seppi 7-6 (7-5) 6-3.

Lucky loser Guillermo Canas beat Czech Jan Hajek 6-1 6-1 to set up a clash with top seed Rodger Federer.

After a tight first set, Roddick stepped up his game in the second and converted one of four break opportunities to seal a clash with Belgian Olivier Rochus, who beat home player Vince Spadea 6-1 6-4.

"Feliciano is a tough player with a lot of spin on his serve and I was having trouble with that early on," said Roddick.

"There are definitely some things I can improve on."

Nadal, 20, also served impressively in his match in a 6-3 7-6 (7-3) victory over Clement, although he had to face six break points.

I'm very confident in my tennis and day by day, I'm getting better Guillermo Canas, who next faces Roger Federer

"I served very well in the first set," said the Spaniard. "I had 10 aces, and I don't do that every day."

In-form Russian 16th seed Mikhail Youzhny was dumped out by Argentine Jose Acasuso 7-6 (11-9) 6-4.

Argentine Canas has been in fine form since his return from a doping ban, culminating in him capturing the Brasil Open title last month.

He got into the men's draw after coming through qualifying.

"I think I'm playing well," said Canas.

"For me, it's great to be here again.

"I'm very confident in my game, I'm very confident in my tennis and day by day, I'm getting better."