Social media reacts to Novak Djokovic's bizarre exit from the 2020 US Open

World No. 1 Djokovic defaults after hitting line judge (1:05)

Novak Djokovic hits a line judge with a ball, defaulting and sending opponent Pablo Carreno Busta to the quarterfinal. (1:05)

Top-seeded Novak Djokovic was defaulted from his fourth-round match at the US Open on Sunday after a ball he hit in frustration struck a line judge, ultimately ending his quest for a 18th Grand Slam title.

The world No. 1 had just lost a game to go down 6-5 to Pablo Carreno Busta in the first set when he haphazardly hit the ball behind him, striking the official who required medical attention.

Djokovic had a 26-0 record in 2020, including a victory at the Australian Open in February. He was the overwhelming favorite at the US Open, in part due to the absence of Roger Federer and defending champion Rafael Nadal.

Fellow athletes and stars had some thoughts on what transpired. Here's a look at some of the comments.

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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. I'm extremely sorry to have caused her such stress. So unintended. So wrong. I'm not disclosing her name to respect her privacy. 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 @usopen 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. Cela ova situacija me čini zaista tužnim i praznim. Proverio sam kako se oseća linijski sudija, i prema informacijama koje sam dobio, oseća se dobro, hvala Bogu. Njeno ime ne mogu da otkrijem zbog očuvanja njene privatnosti. Jako mi je žao što sam joj naneo takav stres. Nije bilo namerno. Bilo je pogrešno. Želim da ovo neprijatno iskustvo, diskvalifikaciju sa turnira, pretvorim u važnu životnu lekciju, kako bih nastavio da rastem i razvijam se kao čovek, ali i teniser. Izvinjavam se organizatorima US Opena. Veoma sam zahvalan svom timu i porodici što mi pružaju snažnu podršku, kao i mojim navijačima jer su uvek uz mene. Hvala vam i žao mi je. Bio je ovo težak dan za sve.

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