Pablo Carreno Busta expresses his shock at Novak Djokovic's US Open exit

Reaction from Pablo Carreno Busta after his opponent, top seed and tournament favourite Novak Djokovic, was defaulted from their fourth-round match at the US Open on Sunday after he accidentally hit a line judge in the neck with a tennis ball.

It was a stunning end to Djokovic’s bid for an 18th Grand Slam title and his 26-0 start to this season.

"In accordance with the Grand Slam rulebook, following his actions of intentionally hitting a ball dangerously or recklessly within the court or hitting a ball with negligent disregard of the consequences, the U.S. Open tournament referee defaulted Novak Djokovic from the 2020 U.S. Open," the U.S. Tennis Association announced.

Djokovic had just lost his serve to Carreno Busta to fall behind 6-5 in the first set when the incident occurred.

As he walked to the sideline for the changeover, Djokovic smacked a ball behind him. The ball hit the line judge, who dropped to her knees at the back of the court and reached for her neck.

After a discussion of several minutes with officials on court, including tournament referee Soeren Friemel, Djokovic walked over to shake hands with Carreno Busta. Chair umpire Aurelie Tourte then announced the default.

There appeared to be no intent on Djokovic's part to hit the line judge as he wasn't looking in that direction when his racquet made contact with the ball, and he was clearly concerned as soon as he realised what had happened.