Electronic line-calling will be used instead of line judges for US Open matches at all courts except the two largest arenas, while singles qualifying and mixed doubles, junior and wheelchair competition are being eliminated entirely.
There also will be three ball people instead of six at courts other than Arthur Ashe Stadium and Louis Armstrong Stadium.
Those are among the changes announced Wednesday by the US Tennis Association as it outlined plans for running a scaled-down, no-spectators version of its Grand Slam tournament in New York City amid the coronavirus pandemic.
"Without question, this is a journey. Things are evolving," new tournament director Stacey Allaster said during a video conference. "We have the plan today. We're in daily contact with both tours."
At a minimum, there will be testing for Covid-19 via nasal swabs upon arrival at what Allaster termed "US Open world," and then once weekly thereafter. If there is the possibility that the tournament "bubble" has been breached by the virus, there could be testing every other day.
It is unlikely players would be asked to sign waivers absolving the USTA of responsibility should they get sick.
The tournament received the go-ahead from the New York state government Tuesday to be held in its usual location in Flushing Meadows, Queens, from August 31 to September 13. In an unusual arrangement, the hard-court tuneup tournament normally held in Cincinnati will be held right before the US Open - and at the Open's site.
There are still lingering questions about which top players will participate, but one made her intentions clear Wednesday: 23-time major champion Serena Williams said she is planning to play at the US Open.
Williams said in a video message that she "cannot wait to return" to the major championship she has won six times. She was the runner-up there each of the past two years.
Among the other changes: Men's and women's doubles will be reduced from 64 teams each to 32, with players who are entered in the singles fields not allowed to enter doubles.
With qualifying cut, each of the 128-player fields for men's and women's singles will include 120 players who get in via their ranking and eight who receive wild-card invitations.
Players will be allowed up to three guests and up to two rooms - one paid for by the player, one by the USTA - at a pair of designated hotels. There also will be the option for players to rent a house outside of Manhattan.
The USTA has not decided exactly how many entourage members will be allowed on-site.
Also Wednesday, the women's and men's professional tours issued what they called "provisional" calendars to resume sanctioned competition in August after being suspended since early March because of the Covid-19 outbreak.
The WTA said its first event would be the Palermo Ladies Open in Italy the week of August 3.
The ATP said its players would return to action at the Citi Open in Washington beginning August 14. That is normally a combined tournament for men and women, but WTA CEO Steve Simon said discussions about his tour's participation was ongoing.
And after that, the ATP-WTA tournament usually held in Cincinnati will be played in Flushing Meadows.
Two tournaments now dropped from the August schedule: the Rogers Cup in Canada and the Winston-Salem Open.
After the hard-court "doubleheader" in New York, the tours will shift to European red clay for tournaments in Madrid and Rome, before the French Open's main draw new start date of September 27.
The WTA said it anticipates all of its upcoming tournaments will be held without spectators but that could change. The ATP is hoping the coronavirus situation will allow for fans at some events.
The French Open already was postponed from May to September because of the pandemic and now is being pushed back an additional week.
The French Tennis Federation says its Grand Slam tournament's main draw will be played at Roland Garros from September 27 to Oct. 11. That doubles the gap from the end of the US Open.
The French Open originally was moved from a May start to September 20. Now its qualifying will begin September 21 and finish on September 25.
The federation says it is working with the French government to "set out suitable measures that will ensure the health and safety of all people present."