Novak Djokovic does not need to worry about accidentally hitting a U.S. Open line judge with a tennis ball this year because there won’t be any line judges. Chair umpires will be the only officials at that tournament’s matches. Hawk-Eye Live electronic line-calling will be used for all courts at the U.S. Open in 2021 and at seven of the nine US Open Series events preceding it. Last year, the USTA relied on the automatic system for the U.S. Open except for at the two main stadiums, Arthur Ashe and Louis Armstrong. During a match at Ashe, Djokovic was defaulted for inadvertently hitting a line judge.
