Less than a week after making it all the way to the final of the China Open, Nick Kyrgios has thrown in the towel at the Shanghai Masters.

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Playing American Steve Johnson, Kyrgios was visibly frustrated throughout the first set, appearing to give up at times.

The Aussie pushed Johnson to 6-6, but the 12 games he was on court were punctuated by angry outbursts and fits of profanity.

He was slapped with a code violation after hitting his ball away in frustration when he successfully challenged the chair umpire.

At the start of the tiebreak, he argued with the umpire over a call, but quickly went up 3-0.

After an epic rally in the sixth point of the tie-break, Kyrgios complained about how tired he was as the crowd became restless.

It was clear he mentally wasn't in the match and remonstrated with the chair umpire on numerous occasions.

Kyrgios was hit with a point penalty in the tiebreak for an audible oscenity.

He then yelled that if he lost the set he would retire from the match in protest at the officiating.

Which he did.

The Australian didn't show any physical signs of struggling and refused medical help at what would have been a change of ends.

Johnson had no idea why Kyrgios walked off.

Stevie Johnson and umpire Fergus Murphy confused and trying to figure out why Kyrgios actually retired after he lost TB 6-7(5). pic.twitter.com/OHK4YCCoII — TroubleFault (@troublefault) October 10, 2017





Kyrgios was fined by the ATP last year for tanking at the same tournament.