Daniil Medvedev suffers devastating blow after loss to Nick Kyrgios

Daniil Medevedev has added reason to be disappointed after his US Open title defence came to an abrupt end against Nick Kyrgios in the round of 16.

Kyrgios booked his spot in the quarter-finals in New York after a superb 7-6 (13/11) 3-6 6-3 6-2 win over Russia's World No.1.

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Medevedev had chances to clinch the first set in a pulsating tiebreak that left viewers in disbelief, before storming back to win the second stanza.

However, the Russian's level began to wane in the third and fourth sets as Kyrgios ruthlessly took advantage.

The Aussie only dropped two games in the fourth set as he set up a showdown against another Russian, 27th seed Karen Khachanov, in the last eight.

Making Medvedev's loss even tougher on the Russian is the fact he will surrender his No.1 ranking to one of Rafael Nadal, Carlos Alcaraz or Casper Ruud - all of whom could leapfrog injured No.2 Alexender Zverev depending on results in New York.

Ruud is already into the quarter-finals after beating France's Corentin Moutet in the round of 16, while Nadal and Alcaraz will be hoping to join him when they face Frances Tiafoe and Marin Cilic at Flushing Meadows on Monday (Tuesday AEST)

Medvedev - who was banned from playing Wimbledon after a controversial rule from All England Club officials - admitted after the loss to Kyrgios that while he was disappointed about losing the No.1 ranking, he was determined to regain his top-ranked status.

Nick Kyrgios overcomes defending champ in style

A dramatic round of 16 encounter has all the usual Kyrgios antics as he seemed to lose his cool during the first set tiebreak, slamming his racket multiple times while repeatedly yelling at members of his entourage.

But he was able to work his way through it, saving three set points, before sealing the opening frame in 64 minutes with his fourth set point.

Kyrgios relied on his dominant serve and limiting his errors, with just one double fault and 11 unforced errors with 21 winners.

The momentum from winning the set kept Kyrgios from spiralling mentally, but he became sloppy in the second, committing four double faults with only three aces, and he had 12 unforced errors with seven winners.

It was the only set he had more than one double fault and more unforced errors than winners.

Medvedev's ability to return in the second set was the difference, lifting his return point success rate from 33 per cent in the opener to 48 per cent to break twice and even up the match.

It had all the makings of a Kyrgios meltdown, but where he would usually begin to unravel and force desperate power shots to shorten points, he instead settled into the battle and refocused on getting into the net.

After only going to the net five times in the second set, he tripled that in the third, winning nine-of-15 attempts while not allowing a single break point opportunity. Kyrgios only created one break point chance for himself, and he took it with aplomb to go up two sets to one.

In the fourth, Kyrgios was able to break again with his first opportunity early on, and with his serve switched on and firing he would only allow one chance for Medvedev to break back, but he snuffed it out before going on to secure a second break and the victory.

Of their five career meetings, Kyrgios has now won four, and he will now get the benefit of the No.1 seed's path through the tournament.

The win also saw Kyrgios become the first player since compatriot Pat Cash in 1987 to beat a World No.1 twice in the same year.

with agencies

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