TOKYO (AP) Fourth-seeded Kei Nishikori beat Donald Young of the United States 6-4, 7-6 (4) on Thursday to advance to the quarterfinals of the Japan Open.
Nishikori, ranked seventh in the world, used his solid baseline game to capitalize on several unforced errors by Young.
With Nishikori leading 4-3 in the tiebreaker, Young double-faulted. Nishikori then ended a rally with a crosscourt forehand to set up match point and closed it out when Young hit a return into the net.
Young had a set point in the second set, but Nishikori held to force the tiebreaker.
''There were some tough moments in the second set, including when he had the set point,'' Nishikori said. ''It wasn't easy. I just tried to save my serve and rely on my forehand. I think I was returning well.''
The 24-year-old Nishikori, who won the Malaysian Open in Kuala Lumpur on Sunday for his third ATP tour title of the season, will take on France's Jeremy Chardy, who ousted seventh-seeded Kevin Anderson of South Africa 6-4, 6-4.
Third-seeded Milos Raonic of Canada booked his spot in the quarterfinals with a 6-4, 6-3 win over unseeded Jurgen Melzer of Austria.
Raonic hit 11 aces in a match that lasted just 1 hour, 14 minutes.
Raonic will play unseeded Denis Istomin of Uzbekistan, who downed qualifier Michal Przysiezny of Poland 6-4, 7-6 (5).
''I felt I played well,'' Raonic said. ''I dealt with adversity well in the second set after going down a break. I served well and took advantage of my opportunities.''
Raonic is on course for a potential meeting with Nishikori in the finals on Sunday. Raonic, ranked eighth, has lost in the final here the previous two years. Nishikori beat him for the title in 2012, while Juan Martin del Potro of Argentina denied him the crown last year.