A serve clock and a warm-up clock will be implemented at the 2018 US Open in a joint initiative aimed at increasing the pace of play.

The rule changes are the result of collaboration and consultation between the United States Tennis Association – which owns and operates the US Open – the ATP and the WTA.

The innovations will also ensure a consistent set of enforcement standards.

In 2017, the US Open utilized a serve clock and a warm-up clock in the Qualifying Tournament as well as in the Junior Tournament, Wheelchair Competition, American College Invitational and Champions Invitational. 

Now both innovations will be rolled out across all men’s and women’s main-draw and qualifying matches. Although the exact location has yet to be determined, a clock will be placed in a position visible to players, fans and the chair umpire.

Along with the US Open, the innovations will also be incorporated at the Citi Open, Mubadala Silicon Valley Classic, Rogers Cup, Western and Southern Open, Connecticut Open and Winston-Salem Open. 


Serve Clock

Players will have 25 seconds to begin their service motion, although a chair umpire will have the ability and discretion to pause the clock. They will have the ability to resume the clock from the same time or reset the clock to 25 seconds.

During a game, this 25-second clock will begin once the chair umpire has announced the score following the previous point. The receiver is responsible for playing to the server’s reasonable pace.

If the player has not started the service motion at the completion of the 25-second countdown, the chair umpire will issue a time violation.

After even-numbered games, the chair umpire will start the clock when the balls are all in place on the server’s end of the court. 


Warm-Up Clock

A one-minute clock will begin when the second player or team entering the court arrives at their chair(s). 

If, at the end of that one minute, a player is not at the net, they will be notified by the chair umpire and subject to a post-match fine, although this will not be a time violation.

A five-minute time clock will begin following the coin-toss and begin the warm-up period. During this time, the chair umpire will make announcements informing the players of the three-minute, two-minute, one-minute, 30-second and end-of-warm-up marks. 

Following the conclusion of the five-minute warm-up period, a one-minute countdown will commence. At the end of this countdown, a player must be ready to play.

If a player is not ready at this juncture, the chair umpire will announce a start-of-match violation, and the player will be subject to a post-match fine. This will not be a time violation.