Rafael Nadal and Roger Federer moved closer to a first US Open meeting with second-round triumphs on Thursday while women's top seeds Serena Williams and Victoria Azaranka also advanced.
Spanish second seed Nadal, a 12-time grand slam winner who has nine titles since ending a seven-month injury layoff in February, beat Brazilian qualifier Rogerio Dutra Silva 6-2 6-1 6-0 in 92 minutes at Arthur Ashe Stadium.
"I was solid with my serve," said Nadal. "I played well. I started a little slower but, when the match was coming on, I felt I played better and better. I am trying to play more aggressive."
Swiss 17-time grand slam champion Federer, at a lowly seventh seeding, fired 37 winners in beating Argentina's 48th-ranked Carlos Berlocq 6-3 6-2 6-1 in 95 minutes.
"I was pretty comfortable out there, so that was a good sign," Federer said. "It's one of those matches I expect myself to win in straight sets and gain confidence in the process. All those things happened so I'm pleased about it."
Federer, who swept the New York hardcourt crowns from 2004-08, and Nadal, whose 2010 US Open title completed a career grand slam, could meet in the quarter-finals.
"I hope I'm going to be there," Federer said. "The biggest mistake I can do is focus on Rafa right now. Clearly I would love a match with Rafa."
With a career-best 17-match hardcourt win streak, Nadal, 27, will next play Croatian Ivan Dodig, who upset him in their most recent meeting in Montreal in 2011
Federer, 32, next faces Frenchman Adrian Mannarino, who defeated US 26th seed Sam Querrey in four sets.
Spanish fourth seed David Ferrer and French eighth seed Richard Gasquet kept rolling towards a potential quarter-final by beating countrymen, Ferrer dispatching Roberto Bautista Agut 6-3 6-7 (5-7) 6-1 6-2 and Gasquet dumping Stephane Robert 6-3 7-5 7-5.
Other second-round winners include 10th seed Milos Raonic, John Isner (13), Janko Tipsarevic (18), Tommy Robredo (19), Philipp Kohlschreiber (22) and Feliciano Lopez (23).
On the women's side, defending champion Williams downed 77th-ranked Galina Voskoboeva 6-3 6-0, and Belarus second seed Azarenka beat Canada's Aleksandra Wozniak 6-3 6-1.
But Italian fourth seed Sara Errani made a tearful exit, the 2012 semi-finalist and French Open runner-up falling to friend and compatriot Flavia Pennetta 6-3 6-1.
"It was difficult," Errani said. "The worst thing was the 'fight'. Normally it's the best thing I do on the court and today it was not good. I don't know why. I think it's the pressure. Everything was very difficult for me."
World No.1 Williams, who would become the oldest US Open women's champion at 31 if she repeats, advanced her quest for a 17th grand slam title and fifth Open crown with ease. She faces Russian-born Kazakh Yaroslava Shvedova next.
Two-time Australian Open champion Azarenka, who beat Williams earlier this month in the Cincinnati final, booked a match against French 26th seed Alize Cornet for a spot in the last 16.
Other winners include No.8 Caroline Wozniacki, Petra Kvitova (7), Angelique Kerber (8), Jelena Jankovic (9), Roberta Vinci (10), Ana Ivanovic (13), Maria Kirilenko (14) and Sabine Lisicki (16).
