Roger Cup: Federer, Nadal, Roddick, Murray in quarters

MONTREAL: Roger Federer, Rafael Nadal, Andy Roddick, Novak Djokovic and Andy Murray qualified for the quarter-finals at the Montreal Masters Roger Cup on Thursday.

Top-seeded Federer avenged a spring loss to fellow Swiss Stanislas Wawrinka with a 6-3, 7-6 (7/5) victory.

Second seed Nadal, playing this week for the first time since May 31 after resting his injured knees, gave his fragile confidence a huge boost with a 6-3, 6-2 defeat of German Philipp Petzschner.

Federer will next play Frenchman and Swiss resident Jo-Wilfried Tsonga, the seventh seed who beat compatriot Gilles Simon 6-3, 6-3.

Nadal showed some signs of nerves with a double-fault on his first match point, but fired home a winner on his second try.

Nadal will face Argentinian sixth seed Juan Martin Del Potro, who rallied to beat Victor Hanescu of Romania 3-6, 6-3, 6-4.

Third seed Andy Murray stayed in touch with his dream of seizing the world number two ranking from Nadal, stopping Juan Carlos Ferrero 6-1, 6-3.

Murray needs to reach the semi-finals, and also hope that defending champion Nadal does not progress into the final four.

Murray has now won all three of his matches with former number one Ferrero, beating the 29-year-old Spaniard on grass this summer at Queen''s and Wimbledon. Victory took 77 minutes as the Scot never faced break point.

Murray will play eighth-seeded Russian Nikol Davydenko, a 7-6 (7/2), 7-5 winner over Chile''s Fernando Gonzalez.

Serbia''s Novak Djokovic, seeded fourth, reached the last eight with a 6-3, 6-4 victory over Russian Mikhail Youzhny.

Djokovic won this event two years ago in Montreal, while Nadal won last year in Toronto as the event alternates between the cities.

Andy Roddick seeded fifth, came good after Fernando Verdasco saved two match points, with the American three-time Wimbledon finalist defeating the tenth-seeded Spaniard 7-6 (7/2), 4-6, 7-6 (7/5).

Roddick will next meet Djokovic after winning their last two meetings, including January''s Australian Open quarter-finals.