Australian bad boy Nick Kyrgios has been hit with a huge fine following his retirement from the first round of the Shanghai Masters against America's Steve Johnson on Tuesday.

Kyrgios quit the match after losing the opening set 7-6, in what seemed to be in protest to the umpiring.

The 22-year-old has several heated discussions with the chair umpire, particularly during the tiebreak, before being heard by the on-court microphones telling his player's box he would retire if lost the first set such was his frustration.

He then made good on is threat and shook Johnson's hand before walking off the court.

Kyrgios has been fined his entire round one prize money of $27,071, plus an additionalย $12,840 for unsportsmanlike conduct.

He has since released a statement apologising to fans for his behaviour and claiming he had a stomach bug and a sore shoulder.

"Guys, I want to apologise to the fans in Shanghai and those that watched around the world on TV today," he said.

"I've been battling a stomach bug for 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.

"My shoulder started to hurt in the practice today which didn't help either and once I lost the first set i was just not strong enough to continue because I have not eaten much in the past 24 hours.โ€

Kyrgios and Shanghai do not seem to mix well, with the Aussie fined and suspended at the same tournament last year for allegedly tanking.