No line judges at US Open in 2021

Novak Djokovic does not need to worry about accidentally hitting a U.S. Open line judge with a tennis ball between points this year because there won't be any line judges — chair umpires will be the only on-court officials at that Grand Slam tournament's matches.

The U.S. Tennis Association and the sport's two leading professional tours, the ATP and WTA, announced Monday that Hawk-Eye Live electronic line-calling will be used for all competition courts at the U.S. Open in 2021 and at seven of the nine US Open Series events preceding it.

A year ago, the USTA relied on the automatic system and dispensed with line judges at the U.S. Open except for matches at the two main courts in Flushing Meadows, Arthur Ashe Stadium and Louis Armstrong Stadium.

During a fourth-round match at Ashe against Pablo Carreño Busta last September, Djokovic was defaulted for inadvertently hitting a line judge in the throat with a ball after dropping a game.

It was a shocking and abrupt stop to the No. 1-ranked Djokovic's 29-match winning streak and his bid to add to his Grand Slam title collection.

After losing a game to trail 6-5 in the first set, Djokovic angrily swatted a ball behind him with his racket — and it went directly at the line judge.

Tournament referee Soeren Friemel ruled the match — and Djokovic's participation in the 2020 U.S. Open — would end there, saying at the time: "We all agree that he didn't do it on purpose, but the facts are still that he hit the line umpire and the line umpire was clearly hurt."

The Australian Open, which Djokovic won in February for his 18th major championship, did not have any line judges on any courts.

Not surprisingly, Djokovic said he approved.

"I actually am in favor of technology. I think it's proven to be very accurate in this particular instance," he said at Melbourne Park when asked about ending the use of line judges. "I don't see a reason why we need the line umpires, to be honest, if we have technology like this."

The US Open Series tournaments that will rely entirely on electronic line-calling this year are the events in Atlanta; Washington; Toronto; Montreal; Cincinnati; Winston-Salem, North Carolina; and Cleveland.

The Cincinnati tournament was held at Flushing Meadows last year right before the U.S. Open as part of a doubleheader of sorts organized because of the coronavirus pandemic and so was played under the same setup.

The USTA said Monday that "upwards of 314,000 calls" were made by Hawk-Eye Live during the two events.

The U.S. Open's main draw begins Aug. 30.