Rafael Nadal and Roger Federer through to quarterfinals of Qatar Open . - The first time in the history of tennis that a player from one country has won all four Grand Slam titles at once. Nadal taken to three sets by unheralded Slovakian Lukas Lacko . Federer also survives scare to beat his close friend Marco Chiudinelli . Second seed Federer also had an early-season workout ahead of 2011 's first grand slam in Australia later this month as he earlier beat fellow Swiss player Marco Chiudinelli 7-6 ( 7-5 ) 7-5 . Defending champion Nikolay Davydenko also seeking to reach the last eight .
Rafael Nadal and Roger Federer through to quarterfinals of Qatar Open . - The first time in the history of tennis that a player from one country has won all four Grand Slam titles at once. Nadal taken to three sets by unheralded Slovakian Lukas Lacko . Federer also survives scare to beat his close friend Marco Chiudinelli . Defending champion Nikolay Davydenko also seeking to reach the last eight .