Novak Djokovic ended his 2020 US Open campaign very, unfortunately, however, he was by far not the first person to hit somebody on the court.
Tennis is a sport where the ball is the thing that matters. Most of the time, people want to know if it fell in the court or if it was already out, however, many times there are also situations when the ball goes out of the court and hits different people in the arena. There are a lot of line judges, ball boys, and cameramen around the court, and so the chance of hitting somebody by an accident is not the smallest. Not only Novak Djokovic experienced this at the 2020 US Open, but it happened also to Roger Federer, Denis Shapovalov, or Aljaz Bedene in the past.
The Swiss Maestro hit a ball boy by an accident at the Australian Open. Federer hit the ball behind the back after the first service, and the ball hit accidentally the ball boy. This resulted in laughs from Federer and also people in the stands. A few years later, Denis Shapovalov hit an umpire during the Davis Cup match against Kyle Edmund from Great Britain. The Canadian was disqualified after this accident.
Not so long ago, Aljaz Bedene played against Daniil Medvedev at the Western & Southern Open. The Slovenian also hit the ball out of frustration and hit the cameraman. However, this time it did not end with default, and Bedene was allowed to continue the match. There were a lot of similar accidents to what happened to Novak Djokovic last night, and it still remains a question if he should have been defaulted or not.