Nick Kyrgios said a stomach bug and a shoulder problem had forced him to retire after losing the first set in his Shanghai Masters first-round match against American Steve Johnson on Tuesday.
The mercurial Australian, who lost to Rafa Nadal in the China Open final on Sunday, took a 4-2 lead in the tiebreak before Johnson fired a series of winners to take the set 7-6(5).
Kyrgios then ran up to his opponent, shook his hand and walked off court to boos from the crowd, leaving Johnson and chair umpire Fergus Murphy confused.
READ | Nick Kyrgios storms off court in Shanghai, days after Beijing meltdown
Local media reported that Kyrgios received two code violations during the set and was docked a point in the tiebreak.
Reports also said he told officials he would quit if he lost the set, but Kyrgios took to Twitter to apologise to his fans.
{{/usCountry}}Reports also said he told officials he would quit if he lost the set, but Kyrgios took to Twitter to apologise to his fans.
{{/usCountry}}“I’ve been battling a stomach bug for the past 24 hours and I tried to be ready but I was really struggling on the court today which I think was pretty evident from the first point,” Kyrgios said.
“My shoulder started to hurt in the practice which didn’t help either and once I lost the first set I was just not strong enough to continue because I’ve not eaten much in the past 24 hours,” he added.
READ | Australian Open tennis officials expecting Serena Williams to defend title
“I’m hoping to be okay for the doubles and will make a decision tomorrow morning, hopefully off of a good night’s sleep which I didn’t get last night.
“I’m gutted to be honest to be honest as I was keen to keep the good momentum that I built in Beijing going and finish the year strong. I’ll do what I can to make sure I do.”
Kyrgios was fined $16,500 by the ATP last year for deliberately throwing a game away during his second-round defeat by Mischa Zverev in Shanghai.
READ| Rafael Nadal routs Nick Kyrgios, seals China Open title in style
Argentine Juan Martin del Potro overpowered Russian teenager Andrey Rublev 6-3 6-4 in the second round.
American Sam Querrey powered past Yuichi Sugita 6-3 6-2 and Canadian teenager Denis Shapovalov beat Viktor Troicki 6-7(3) 6-3 6-0 in first-round matches.