Second seed Tomas Berdych and third-seeded Serb Janko Tipsarevic highlighted Thursday's second-round winners at the $1.28 million Japan Open Tennis Championships.
The Czech slugger Berdych handled Colombian Alejandro Falla 6-3, 7-5, while Tipsarevic whipped Swiss qualifier Marco Chiudinelli 6-4, 6-2 on the hardcourts at Ariake Colosseum.
The 2008 Tokyo champion Berdych will face Japan's Kei Nishikori on Friday, while Tipsarevic's quarterfinal opponent will be big-serving Canadian Milos Raonic.
A Day-4 upset occurred when Cypriot Marcos Baghdatis bounced fourth-seeded Argentine Juan Monaco 7-5, 1-6, 6-3. The four-time 2012 ATP champion Monaco was fresh off his title in Kuala Lumpur last week.
Also on Thursday, a sixth-seeded Raonic was leading Viktor Troicki 3-0 in the opening set when the Serb retired, the eighth-seeded heavy crowd favorite Nishikori got past Spanish veteran Tommy Robredo 5-7, 6-1, 6-0, and Russian qualifier Dmitry Tursunov took out Japanese wild card Tatsuma Ito 7-5, 6-3 following a rain delay. Tursunov will meet Baghdatis on Friday.
One other quarterfinal will pit top-seeded and defending champion Andy Murray against seventh-seeded Swiss Stanislas Wawrinka. The U.S. Open titlist and Olympic gold medalist Murray beat 2010 champ Rafael Nadal in last year's Tokyo finale.
The winner of this event will claim a first prize of $308,000.