Defending champion and home favorite Shang Juncheng claimed his first match win since returning from a foot operation, after battling past Belgium's Zizou Bergs 6-1, 5-7, 6-4 at the ATP Chengdu Open on Wednesday.

China's Shang, who did not compete from January until late July due to a foot injury that led to surgery in March, dug deep to hold off World No. 46 Bergs, registering his first match win since returning to action two months ago.

The left-hander saved six of seven break points, according to Infosys ATP Stats, highlighting a gutsy performance for the 20-year-old in his first head-to-head meeting with Bergs on the Tour.

Up a break in the third set, World No. 138 Shang crucially rallied from a 40-0 deficit to hold serve, extending his lead to 5-3 before holding to love in his next service game to close out the three-set triumph.

Shang's next opponent will be World No. 33 Brandon Nakashima, after the fourth-seeded American received a bye into the round of 16 at this event in the capital of Sichuan Province.

China's Zhou Yi also enjoyed a memorable start to his campaign in Chengdu after upsetting World No. 34 Cameron Norrie in three sets.

The 20-year-old saved match point while trailing 40-30 in the 10th game of the third set, before shocking the Briton 6-7, 6-4, 7-6 for the biggest win his career, in terms of the world rankings.

World No. 304 Zhou will face Australia's 103rd-ranked Christopher O'Connell in the round of 16.

Another high-profile Chinese player, Wu Yibing, edged France's Adrian Mannarino 4-6, 7-6, 7-5 to reach the last 16 at the ATP Hangzhou Open.

The World No. 196 will meet Australia's 76th-ranked Adam Walton or the USA's World No. 79 Sebastian Korda in the next round in Zhejiang Province.