Former champion Tomas Berdych comfortably beat Colombia's Alejandro Falla 6-3, 7-5 to reach the quarter-finals of the Japan Open on Thursday.
Czech Berdych, who won the Japan Open in 2008, played well within himself, blasting nine aces as he rolled through in one hour, 18 minutes to notch his 50th win of the year.
"I served well and took my chances," the second seed told reporters after moving another step closer to qualifying for the season-ending World Tour Finals.
"I'm not there yet," added the world number six, referring to the next month's eight-man London shootout.
"I need to keep playing well and stick to my tennis. Not talk about it but bring my best game and that's the best way to qualify."
Berdych will face either Spain's Tommy Robredo or local favourite Kei Nishikori, the eighth seed, in the last eight of the $1.2 million hardcourt event.
Third seed Janko Tipsarevic also booked his spot in the quarter-finals with a 6-4 6-2 victory over Swiss qualifier Marco Chiudinelli.
The Serb faces sixth seed Milos Raonic next after Tipsarevic's compatriot Viktor Troicki retired against the Canadian with a calf injury at 3-0 down in the first set.
US Open champion and Tokyo title holder Andy Murray enjoyed a day off before the top seed takes on Switzerland's Stanislas Wawrinka in their last eight encounter on Friday.
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