KUALA LUMPUR, Sept. 12 -- Lee Zii Jia's coach Liew Daren has faced a wave of online criticism after the Malaysian shuttler suffered a shock early exit from the Vietnam Open.

The backlash came after Zii Jia's defeat by Taiwan's world No. 88 Wu Zhe-ying in the second round of the Super 100 tournament, with The Star reporting that Daren shared one particularly harsh comment on his personal social media account.

"Oii you better quit from Team Lee Zii Jia, you are the most useless coach he can get," the badminton fan wrote.

The same individual later criticised Daren again in response to another Instagram post, alleging that the coach's advice had contributed to Zii Jia's recent poor performances.

Daren took charge of coaching Zii Jia in Ja...