Novak Djokovic raced into the quarter-finals of the China Open with a 55-minute win over home hope Zhang Ze.
The world number one took his record in Beijing to 26-0 in five visits as he beat China's number one 6-2 6-1.
Djokovic, 28, goes on to face Australian John Millman or American John Isner in the last eight.
Croatia's Ivo Karlovic became the all-time leader in aces as he hit 26 to reach 10,247, passing compatriot Goran Ivanisevic's record of 10,237.
"It's a great feeling," said 36-year-old Karlovic. "For the past year I knew it was possible and I was hoping that it would be this year.