Khachanov outlasts Kyrgios in late-night thriller, advances to final four at US Open

Despite playing some of the best tennis at this year's event, Nick Kyrgios was unable to power past Karen Khachanov as the Russian prevailed in a lengthy battle to reach the US Open semifinal.

Khachanov fought past the title favorite in a 7-5 4-6 7-5 6-7(3) 6-4 victory, relying on his consistency and firepower to overcome the Australian. With no love lost between both men, sparks were expected to fly in their quarterfinal encounter as each tried to overpower the other.

Both competitors relied heavily on their serves, with Khachanov hitting 30 aces to 31 by his opponent. With very little to separate both men, it came down to consistency. Although Kyrgios hit 75 winners, the Wimbledon finalist also committed an astounding 58 unforced errors. This was significantly less than his 27th-seeded opponent, who hit only 31 unforced errors to 61 winners.

Although the crowd was firmly behind Kyrgios, the Aussie was unable to limit his errant shots as Khachanov surprised the crowd with some amazing defensive plays. After obtaining the crucial break at the start of the final set to lead 2-0, the former World No.8 never looked back, sealing his victory after a marathon three hours and 39 minutes.

Awaiting Khachanov in his maiden Grand Slam semifinal is Casper Ruud, as the fifth seed made short work of Matteo Berrettini to reach the final four.