New York, USA, 5 September 2022 | Matt Trollope

Nick Kyrgios has produced an inspired performance to knock world No.1 and defending champion Daniil Medvedev out of the US Open.

The Australian star advanced to his first quarterfinal in New York, courtesy of a 7-6(11) 3-6 6-3 6-2 triumph under lights at a sold-out Arthur Ashe Stadium on Sunday night.

Kyrgios came through an enthralling tiebreak, then overcame a second-set lapse, to dominate the affair, improving his head-to-head record against the Russian to 4-1.

“It was an amazing match. Obviously Daniil is defending champion, a lot of pressure on his shoulders. But I played really well. I’ve been playing amazing the last couple of months,” Kyrgios said on court.

“What a place to do it – packed house in New York. I’m extremely blessed.”

After going seven-and-a-half years without appearing in a major quarterfinal, Kyrgios has now notched two in a row, after reaching the same stage at Wimbledon – where he ultimately progressed to the final – in July.

He will next face Karen Khachanov, who earlier upstaged Pablo Carreno Busta in five sets, for a place in the semifinals.

“I take it one match at a time. Obviously that belief came from Wimbledon … that final (loss to Novak Djokovic) was a hard pill to swallow,” said Kyrgios, who is projected to rise to world No.18 as well as reclaim the Australian No.1 ranking.

“Khachanov is a great player, he’s a great fighter, we’ve had some absolute battles.

“I’m just glad I’m finally able to show New York my talent. I haven’t had many good trips here, to be honest, I haven’t played great tennis.

“So I’m really glad that I’m able to show you guys the work, and the dedication, finally. Took me 27 years.”

The pair’s head-to-head record laid fascinating foundations for this fourth-round blockbuster; Kyrgios led the series 3-1, but Medvedev had won their only Grand Slam battle, earlier this season at Australian Open 2022.

Perhaps most tellingly, Kyrgios had beaten Medvedev just a few weeks ago at the Montreal Masters, and continued that good form against the world No.1 on Sunday night in New York.

He threatened to break in Medvedev’s very first service game, and while he missed that chance, he broke in the sixth game for a 4-2 lead, pumping the crowd up in the process.

Medvedev was up for the fight, breaking back immediately and gesturing for the crowd to give him some support in return.

Fittingly, the set progressed to a tiebreak – and it is one people will be talking about for years to come.

Kyrgios built leads of 4-1 and 5-3, but Medvedev worked his way back into contention and would go on to earn three set points – two of which Kyrgios saved with magnificent winners.

The Australian then earned three set points of his own – only for Medvedev to erase them all.

Undeterred, Kyrgios created a fourth set point with an inspired drop shot winner which drew a deafening roar from the crowd.

And he converted it, off a Medvedev error, to clinch the tiebreak 13-11.

An energy lapse followed, on which Medvedev capitalised, and in the blink of an eye the top seed was ahead 5-1 in the second set.

But a re-enegised Kyrgios staged a late rally to close the gap, and despite losing the set, he was back to his urgently aggressive best in sets three and four.

He broke the world No.1 in the fourth game of the third on his way to a 4-1, an unassailable advantage.

And he broke again in games three and five of the fourth to completely take control.

Between those breaks, in the fourth game, Kyrgios encountered resistance; this was the defending champion, after all.

But facing break point at 30-40, Kyrgios stepped up, pounded back-to-back aces, then forced a return error – an escape with an exclamation point.

Medvedev’s body language was indicative of a player who knew his opponent was too strong.

And Kyrgios proved that to be correct, pounding a 21st ace on match point to complete a famous victory – his first over a world No.1 at a Grand Slam since he beat Rafael Nadal, when still a teenager, at Wimbledon in 2014.

“I’m still trying to figure it out (about what clicked recently), honestly,” said Kyrgios, who since Roland Garros has won more matches than any other player on the men’s tour.

“I’m just trying to work hard every day, trying to make every practice session count, getting to sleep. I would probably be out every night, before.

“My team, it’s all my team. I’m just really happy and hopefully I can keep it going. I’m just working really hard.

“I just don’t want to let them down. We’ve been on the road now for four months, and we’ve all got families that we want to see, and I want to make it count.

“This is the last trip before I head back to Australia, so I want to go all the way. Hopefully it’s possible.”