Usain Bolt has reacted with surprise at receiving a notice for a drugs test from Australia's anti-doping authority, saying he is "not even a professional footballer yet".
The eight-time Olympic sprint champion was nonplussed by ASADA ordering him to undergo a test, while he continues a trial with A-League club Central Coast Mariners.
Bolt, who retired from athletics last year, scored twice on his first Mariners start in Friday's friendly against Macarthur South West, but then reacted quizzically to receiving the drugs test notice on Monday.
Bolt said in an Instagram story: "So guys I've retired from track and field looking to become a footballer but look at this. How am I going to get a drug test today? I'm not even a professional footballer yet. Seriously."
In the video, Bolt produced a piece of paper which appeared to show ASADA's notice requesting blood and urine had been issued by Football Federation Australia.
Bolt added: "So I asked the lady, 'Why am I getting drug tested when I haven't signed for a club yet?' and she said they told her I'm an elite athlete so I have to get tested. Okay then."
The 32-year-old's Mariners team-mate Ross McCormack, meanwhile, has hailed the 100m and 200m world record-holder's chances of succeeding in his switch to football.
Scotland international forward McCormack is on loan at the A-League side from Aston Villa and has been playing alongside the Jamaican sprint king.
"He is an absolute specimen of a human being. Huge, 6ft 5in tall and his shoulders seem about three metres wide," McCormack told the Daily Mail.
"His transformation just since I've been here is massive. He needed a different type of fitness. He's used to being explosive and running in straight lines. He's had to get used to stopping and checking and building his stamina.
"If he pulls it all together he can be some threat. He can bump guys off easily with his strength, he's got aerial presence and then there's the fear factor of his pace. Defenders won't want to allow him to turn or run behind them because they know they won't catch him.
"The great thing is Usain's so humble. You forget you are with a global icon. He stays behind to work after training and asks for advice yet, when he talks, it's a bit like John Terry at Aston Villa last season, everyone in the dressing room wants to listen."
