'I didn't show up at all': Nick Kyrgios hits back shamelessly after tanking at Shanghai Masters

Kyrgios shocked the world of tennis in his match against Mischa Zverev as he barely put in any effort - with the umpire even warning him about his conduct after a bunted a serve over the net while trying to defend a break point.

Rather than show any remorse for his antics, he instead went on the defensive after the match.

"Just took the easy way out tonight and obviously didn't show up at all," he said, after claiming to have been "physically and mentally tired" after "a lot of matches in a row".

"I wasn't so much frustrated. I just tapped out a little bit, I guess."

At one point Kyrgios told the umpire "Can you call time so I can finish this match and go home?". Later, as qualifier Zverev prepared to serve for the match, Kyrgios picked on a spectator, saying, "'You wanna come here and play? Sit down and shut up and watch."

The booing that preceded and followed that incident didn't appear to have fazed the Aussie at all.

"Not at all. I feel like if they knew what they were talking about they'd be on the tennis court and being successful as well," he said.

"I can't really understand it at all. They don't know what I'm going through, so no, I don't understand it.

"I don't owe them anything. It's my choice. If you don't like it, I didn't ask you to come watch. Just leave.

"If you're so good at giving advice and so good at tennis, why aren't you as good as me? Why aren't you on the tour?

"You want to buy a ticket? Come watch me. You know I'm unpredictable. It's your choice. I don't owe you anything. Doesn't affect how I sleep at night."

Kyrgios was asked about how defeat had hurt his chances of qualifying for the season-ending ATP World Tour Finals in London next month.

"I couldn't care less, to be completely honest with you," came the reply.

Later, on Twitter, it seemed that Kyrgios had changed his mind, saying. "Not good enough today on many levels, I'm better than that. I can go on about excuses but there are none. Sorry."