The defending champion, who won his 14th straight match against Jiri Lehecka 6-2, 7-6 [8-6], will take on Andrey Rublev or Chinese wildcard Bu Yunchaokete.
The 23-year-old is being closely watched after the World Anti-Doping Agency (WADA) said on Saturday that it was requesting a two-year ban after he tested positive twice for clostebol traces in March.
#sinner #chinaopen