Nick Kyrgios' controversial career took another turn on Monday night when he was pictured wearing a 'F*** Donald Trump' T-shirt at a press conference in Sydney.

The Australian changed into the top, which also displayed a picture of the US President complete with devil horns, shortly after defeating Rafael Nadal in five sets in a Fast4 exhibition match in his homeland.

When asked about wearing the T-shirt, Kyrgios told the Australian media: "It's pretty explanatory."

The 21-year-old, currently managing a knee injury ahead of the start of the Australian Open next week, returned to his dressing room and changed back into his branded sports top after the interview.

Kyrgios has hit the headlines for the wrong reasons on several occasions during his brief career.

He was fined twice by the Association of Tennis Professionals, firstly for an on-court remark about Stan Wawrinka's girlfriend during their Rogers Cup match in Montreal in 2015 and then a year later for his behaviour during a defeat to qualifier Mischa Zverev at the Shanghai Masters.

Kyrgios also pulled out of the Rio Olympics last year due to an ongoing row with the Australian Olympic Committee.