Former Australian Rugby League Football player Matthew Johns has called out rising Nick Kyrgios.
Kyrgios, 22, exited the Shanghai Rolex Masters after his surprising round one retirement.
American Steve Johnson claimed the first set against Kyrgios with a 7-5 tie-break score.
The Australian immediately walked to the net -- shook hands with Johnson -- grabbed his bag and left the court booed off.
The world No. 21 was frustrated with the chair umpire and Shanghai crowd during the match.
Kyrgios was reportedly heard saying he would retire if he loses the first set.
He later provided a statement on the social media claiming he wasn't feeling his best due to a stomach bug.
The Australian was fined by just over $31,000 for his Shanghai meltdown.
"It's embarrassing behavior," Johns told Triple M. "It's offensive, the deliberate lack of effort from this individual. This bloke ... it’s just disgraceful behavior. People pay good money to watch this match. He tells supporters courtside that if he loses the first set he’s going to walk off, does it, then tries to go and apologize on Twitter saying he’s got a tummy bug. Please."
Also read: Nick Kyrgios loses 30k for Shanghai walk-off