Russia's Daniil Medvedev ( checks on Australia's Nick Kyrgios Photo: AFP

Russia’s Daniil Medvedev (
checks on Australia’s Nick Kyrgios. Photo: AFP

WATCH: Kyrgios involved in weirdest point in tennis history?

Nick Kyrgios made a bizarre error in judgement during the US Open, conceding a point in a fashion that you have to see to believe.

Russia's Daniil Medvedev ( checks on Australia's Nick Kyrgios Photo: AFP

Russia’s Daniil Medvedev (
checks on Australia’s Nick Kyrgios. Photo: AFP

Ultimately, Australian firebrand Nick Kyrgios sent defending champion Daniil Medvedev tumbling out of the US Open on Sunday as he powered his way to another memorable victory.

READ | KYRGIOS STUNS MEDVEDEV AT US OPEN, GAUFF ADVANCES

The 23rd-seeded Kyrgios produced some scintillating shot-making on his way to a 7-6 (13/11), 3-6, 6-3, 6-2 win over the world number one from Russia.

However, it could have all so easily gone awry for Kyrgios when he bizarrely gave away a point during the early stages of the all-important third set.

Having got himself in a certain position to win a point that would have earned himself a break point, Kyrgios strangely ran onto the opposite side of the court to hit a ball that was clearly going to land well out.

Kyrgios thought he may have got away with winning the point, but it was correctly called out as a foul, and the Australian laughed at his error after the game.

“I think I had probably the most boneheaded play of all time tonight. I thought it was legal to be honest. I genuinely thought it was legal,” Kyrgios said in an interview with ESPN. “I thought I was playing the concrete streets of my suburb in Canberra. That’s something I would do there and I realised that it wasn’t legal. You can see my face… I was so happy. I was like, ‘That’s the best shot ever’ and it wasn’t legal. But it was fun.”

READ | PERFECT NADAL INTO US OPEN FOURTH ROUND

Kyrgios admitted he was relieved to have secured another victory

Kyrgios will face Karen Khachanov in the quarter-finals on Tuesday

“It’s a great win. But I come off the court and I’m just almost relieved that it’s over because there’s just so much pressure every time I go out on court, so much expectation, so much unpredictability of what I can do,” Kyrgios said. “I just sit there in the locker room after and I’m just super proud of the performance because there was really a time where I didn’t think I was capable of producing and doing this any more.”

ALSO READ | MAJOR SETBACK FOR NICK KYRGIOS IN ASSAULT CASE