TENNIS: Australian Nick Kyrgios is under investigation by the sport's governing body after his latest on-court meltdown.
The ATP Tour is investigating Kyrgios' explanation after he stormed off after losing the first set of his first-round match in Shanghai on Tuesday.
The 22-year-old said his retirement was due to a stomach upset rather than a protest over umpiring.
The ATP has however docked Kyrgos his first-round prizemoney of $27,000 for failing to undergo a medical after the match and fined him $US10,000 for unsportsmanlike conduct.
It is the fourth time this year 22-year-old has pulled out of a match and tennis officials said he could yet face further punishment from the ATP.
The world No.21 had argued with spectators and was accused of giving away points in a defeat at the same Shanghai event last year. He was consequently suspended.
Kyrgios' immediate playing future is again under threat following his latest retirement which came after he lost the first-set tie break to American Steve Johnson.
If the governing body determines Kyrgios' explanation is not convincing, he could be banned for several weeks for a code of conduct breach.
Kyrgios took to social media to apologise for this latest controversy. In a statement posted on Twitter a few hours later he said that he had a "stomach bug” and had hurt his shoulder. The tweet later appeared to have been deleted.
Kyrgios' exit came after he complained about the umpire and spectators in the arena. He was then docked a point penalty for the second match running because of his conduct, which included belting a ball out of the court in a flash of rage.
"What's happening here?” he was overheard saying, seemingly irritated by spectators moving around between.
"Exactly why I shouldn't come here.
"Poor officiating again. Sick of this place.”
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