An already unusual U.S. Open took an unimaginable turn Sunday when No. 1 seed Novak Djokovic was disqualified from the tournament after unintentionally hitting a lineswoman with a ball early in his fourth-round men’s singles match against No. 20 seed Pablo Carreño Busta.

Djokovic, a 17-time Grand Slam winner and the top-ranked player in men’s tennis, is out of the tournament, and Carreño Busta will advance to the quarterfinals. Djokovic’s default ensures men’s tennis will have a new Grand Slam champion for the first time in six years.

The incident occurred 40 minutes into the match at Arthur Ashe Stadium in New York. Djokovic trailed 6-5 in the first set and had shown some frustration with his play. The Serbian missed a passing shot from Carreño Busta on his forehand side, a winner that gave the Spaniard the opportunity to serve out the set. In preparing for the subsequent changeover, Djokovic took a spare ball out of his pocket and, apparently without looking, hit it with his racket toward the back of the court, where it struck a lineswoman in the throat and she fell.

Djokovic rushed to check on the lineswoman, who later walked off the court apparently in distress. He then spoke at length to tournament officials, including referee Soeren Friemel, before he was disqualified in accordance with the “abuse of balls” statute in the Grand Slam rule book.

“Players shall not violently, dangerously or with anger hit, kick or throw a tennis ball within the precincts of the tournament site except in the reasonable pursuit of a point during a match (including warm-up)," the rulebook states. “…Abuse of balls is defined as intentionally hitting a ball out of the enclosure of the court, hitting a ball dangerously or recklessly within the court or hitting a ball with negligent disregard of the consequences”

In a statement, the U.S. Tennis Association confirmed that Djokovic will lose the $250,000 in prize money he earned for reaching the fourth round of the tournament, plus an additional $10,000.

Djokovic left Billie Jean King National Tennis Center shortly after the incident and did not speak with reporters, instead posting an apology on Instagram hours later.

“This whole situation has left me really sad and empty. I checked on the lines person and the tournament told me that thank God she is feeling ok," Djokovic said. “I’m extremely sorry to have caused her such stress. So unintended. So wrong. ... As for the disqualification, I need to go back within and work on my disappointment and turn this all into a lesson for my growth and evolution as a player and human being. I apologize to the U.S. Open tournament and everyone associated for my behavior. I’m very grateful to my team and family for being my rock support, and my fans for always being there with me. Thank you and I’m so sorry.”

Friemel, the tournament referee, said in an interview on ESPN that it took about 10 minutes of discussion on court to determine if Djokovic should be disqualified because he had no intention to hit the lineswoman. Friemel said he was positive he “got the facts right” in issuing the default.

“His case was that he didn’t do it on purpose and that we had to take this into consideration, which obviously we did,” Friemel said. “But in this situation, the result of his action was that — overwhelming — the line umpire was clearly hurt, clearly in pain. She went down. Taking this into consideration, there was no other option than to default Novak.”

Carreño Busta, who will face Denis Shapovalov in the quarterfinals, said in a news conference that his back was turned when Djokovic hit the ball and he was stunned when he realized what was going on.

“Of course I was in shock because I never expect this moment,” he said. “I just tried to be calm because I don’t know what is going to happen, if we can continue or if we finish the match. Finally we finish, and I continue, really, in shock.

“I think this was not intentional. I don’t think that any one of us, of the players, do this kind of thing intentional. It’s just the moment. It’s just I broke [his] serve, and, you know, he threw the ball. I think that it was bad luck. You cannot do this, but of course I think that Novak never, never wants to hit the line umpire. ... Well, rules are the rules. The referee and the supervisor did the right thing but is not easy to do it."

While it is rare for players to make contact with an on-court official, it has happened and resulted in memorable disqualifications.

In 2017, a then-teenage Shapovalov was defaulted from a Davis Cup match when he spiked a ball in anger and accidentally hit a chair umpire in the eye. In 1995, Tim Henman of Britain was defaulted from a doubles match at Wimbledon after hitting a ball into the head of a ball kid.

The U.S. Open, of course, is no stranger to on-court controversy. Naomi Osaka won her first Grand Slam at Arthur Ashe Stadium in 2018 after her opponent, Serena Williams, received a contentious game penalty that churned discussion for weeks.

“I mean, look, it’s unfortunate. He hit a ball. He hit a tennis ball. It’s very unfortunate that, you know, he hit the line judge and especially where it hit her,” No. 5 seed Alexander Zverev said in a news conference shortly after the incident. "... I think he’s going to be a little bit upset about it, but, yeah. He could have — if he would have hit it anywhere else, if it would have landed anywhere else, we are talking about a few inches, he would have been fine.”

Djokovic was the runaway favorite to take home the title in New York and earn his 18th Grand Slam championship. The 33-year-old had not yet lost a match in 2020, compiling a 26-0 record. He had dropped only one set in his first three matches of the tournament.

With Djokovic gone, Rafael Nadal sitting out because of travel concerns amid the novel coronavirus pandemic and Roger Federer absent after shutting down his season following knee surgery, the men’s draw is more open than it has been in years at any major tournament. A first-time Grand Slam champion will be crowned for the first time since 2014, when Marin Cilic won his only major title at the U.S. Open.

Of the 48 Grand Slam finals contested since Djokovic won his first major title at the 2008 Australian Open, only eight have gone to men not named Djokovic, Federer or Nadal: Andy Murray and Stan Wawrinka each have three, and Juan Martin del Potro and Cilic have one apiece.

“Now it gets interesting,” Zverev said. “Now I think is the time where it gets really interesting. Yeah. I know who is where in the draw. I know who I can play. I know who the rest of the guys can play. We’ll see where we go from here.”

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