PARIS, France (AFP) — Defending champion Novak Djokovic and fourth seed Andy Roddick both reached the quarter-finals of the ATP Swiss Indoors after straight sets wins here yesterday.

Second seed Djokovic won, 6-4, 7-6 (8/6), against Finn Jarkko Nieminen, a losing finalist in 2007, having registered seven aces and converted a single break of serve.

Roddick dealt with an unknown quantity in Kazakh Andrey Golubev, winning, 6-3, 6-4.

Djokovic, who interrupted the three-year title streak of Roger Federer here in 2009, will compete for a semi-final place against Dutchman Robin Haase. Roddick takes on David Nalbandian, whom he last faced in 2006.

Nalbandian, the 2002 champion, reached the quarter-finals of one of his favourite events by upsetting Croatian sixth seed Marin Cilic, 4-6, 6-4, 6-4.

Radek Stepanek will line up as the next opponent for Federer, with the Swiss home favourite and top seed hoping he can still do no wrong after two imposing victories at the hall where he got his start in the sport as a teenage ballboy.

Stepanek booked his place in the next round by beating Colombian Santiago Giraldo 3-6, 6-2, 6-0.

Serb Viktor Troicki advanced without firing a shot when Frenchman Paul-Henri Mathieu was forced to forfeit due to lower back pain.

But Richard Gasquet earned a victory as he bids for a place in the French Davis Cup finals team against Serbia next month, beating German qualifier Tobias Kamke, 6-4, 7-5.