Grigor Dimitrov won the final five games to defeat Juan Martin del Potro and reach the quarter-finals of the China Open.
US Open semi-finalist Del Potro was a break up in the first set and served for the second but Dimitrov fought back for a 7-6 (8/6) 7-5 victory.
The third seed next plays fifth seed Roberto Bautista Agut, who was on course for a double bagel when Aljaz Bedene retired with a knee injury, trailing 6-0 4-0.
Nick Kyrgios recovered from a set down to see off Mischa Zverev 3-6 6-2 6-2 in an hour and 21 minutes.
Zverev was Kyrgios' opponent in Shanghai 12 months ago when he showed such a lack of commitment, while arguing with the umpire and disgruntled supporters, that he was banned by the ATP.
There was a lack of urgency from the Australian, who was filmed singing along to a pop song at one change of ends, in the first set but he responded well and will play Belgium's Steve Darcis in the last eight.
That will be a rematch of their Davis Cup semi-final clash, which Kyrgios won in five sets, although Belgium claimed the overall spoils.
At the Japan Open, top seed Marin Cilic booked his place in the quarter-finals with a 6-3 6-4 victory over home wild card Yasutaka Uchiyama.
He next takes on America's Ryan Harrison, who dented US Open finalist Kevin Anderson's hopes of qualifying for the ATP World Tour Finals with a 6-3 1-6 7-6 (7/2) win.
Eighth seed Diego Schwartzman beat Bernard Tomic 6-3 6-1 while, in the first round, fourth seed David Goffin kept his winning run going after lifting the Shenzhen Open trophy with a 7-5 6-1 victory over Feliciano Lopez.
Source: PA
