Kyrgios slammed for on-court outburst during five-set win over Seppi at Oz Open

Australian teen tennis ace Nick Kyrgios has been slammed for his on-court attitude during his five-set thriller against Italy's Andreas Seppi at Melbourne Park on Sunday.

Kyrgios, who defeated Seppi 5-7, 4-6, 6-3, 7-6 (7-5), 8-6 to become the youngest Australian Open men's quarterfinalist in almost 25 years, launched expletive-laden outbursts at fans, while he also hammered ball kids, line officials and the umpire during his match.

Kyrgios, who is the first native to reach the final eight since Lleyton Hewitt a decade ago, drew the rage of social media users, particularly for swearing at members of the crowd, including a person using their mobile phone, Stuff.co.nz reported.

During the crucial fourth set he yelled at the person asking him to get off his 'f---ing phone'. He has already been fined 4926 Australian dollars for racket abuse and audible obscenities during his first-round match last Monday.

Kyrgios could be fined again because television viewers heard his expletive outburst after his temper boiled over at the end of the second set when he slammed his racket into the ground, nearly breaking it in two.

But Kyrgios, who has become the poster boy of the Australian Open, recovered to defeat Seppi in three hours and 34 minutes, with a new racket in hand. However, his antics on the court left many unimpressed despite his stellar comeback.

A Twitter user posted that he knows there's a lot of pressure, but screaming at the ball boys or girls for ones towel isn't cool. Another tweeted that just once he wishes Australians would see people as 'a****les even when they have won, adding that it seems winning excuses disgusting behaviour.