Nadal leads the hunt for quarter-final slots

PARIS, June 4 (Reuters) Four more men's quarter-final berths are up for grabs at the French Open today as the business end of the tournament begins.

Spain's Rafael Nadal, who turned 21 on Saturday, continues his quest for a hat-trick of Roland Garros titles when he takes on Australia's Lleyton Hewitt in the day's standout match.

Rising Serb Novak Djokovic survived a nailbiting third round match against French wildcard Olivier Patience on Saturday and the sixth seed, strongly tipped to break the Nadal-Federer stranglehold on tennis, takes on Fernando Verdasco.

Should Djokovic win he will equal his performance of last year when he retired injured against Nadal in the last eight.

Unseeded Verdasco is one of four Spaniards still in contention for the men's crown. Another is 1998 champion Carlos Moya. The 30-year-old Moya faces another veteran, 35-year-old Swede Jonas Bjorkman, for a place in the quarter-finals.

Bjorkman is the oldest player to reach the fourth round since 38-year-old Italian Nicola Pietrangeli performed the feat in 1972.

In the day's other fourth round match, Igor Andreev will try and follow his compatriot Nikolay Davydenko into the quarter-finals when he plays Cypriot Marcos Baghdatis.

Should Andreev win, it would mean two Russian men have made the quarter-finals at Roland Garros for the first time since Yevgeny Kafelnikov and Marat Safin in 2000.

As well as Davydenko, three other men, top seed Roger Federer, Argentine Guillermo Canas and Spain's Tommy Robredo, are already in the quarters.

REUTERS TB HS1128