Novak Djokovic has been disqualified from the US Open after hitting a line judge with a ball.

The world No1 was contesting a fourth-round match against Pablo Carreno Busta on Sunday when the incident occurred.

Spaniard Carreno Busta had just moved into a 6-5 first-set lead and Djokovic showed his frustration by hitting a ball away from the court.

It appeared to strike a lineswoman in the face, and although 17-time Grand Slam champion Djokovic moved quickly to apologise for the accident, which saw the judge drop to the floor, officials decided the Serb would be defaulted from the match. The 33-year-old pleaded his case for some minutes before ultimately departing from the court.

As a result of the three-time US Open champion exiting the tournament, Carreno Busta now moves into the quarter-finals.

US Open organisers said in a statement that Djokovic would lose any rankings points earned at the event and be fined all of his prize money from the competition. The Serb could also face further fines for the incident, which was deemed to amount to “hitting a ball with negligent disregard of the consequences”.

Top seed Djokovic, who left the grounds without speaking to press, was 26-0 in 2020 before the fourth-round clash. 

His departure from Flushing Meadows means the US Open will crown a first-time men’s Grand Slam winner for the first time since 2014. That year, Marin Cilic lifted the singles trophy after defeating Kei Nishikori in the final.

This year, the New York tournament was already without 19-time Slam champion Rafael Nadal – who declined to participate due to fears over the coronavirus crisis – and 20-time major winner Roger Federer, who is recovering from injury.