However, the Thai player was made to slog for 48 minutes before winning 23-21, 21-7 in the match played at the Olympics Sports Centre Gymnasium in Changzhou.

Kunlavut has now beaten the 26th-ranked Jun Hao in all three encounters with him so far.

He will meet the winner of the match between Taiwan’s Chou Tien Chen and HS Prannoy from India in the quarter-finals.

Jun Hao was the lone Malaysian representative in the men’s singles event as Lee Zii Jia had withdrawn due to an injury.

Jun Hao only made the quarter-finals once this year, with six first-round and four last-16 exits

He wins a cash prize of US$6,000 (RM25,300) for making it to the second round.

The China Open is a World Tour Super 1000 event which offers a total cash prize of US$2 million (RM8.4 million).