Shot clocks will be used in all ATP Tour tournaments out of 2020.

The clock – which counts down the 25 seconds allowed between points – had been trialled at the nextgen ATP Finals in 2017 and was first used at a Grand Slam at the 2018 US Open.

World number two Rafael Nadal previously criticised the device and said it could “ruin the entertainment variable” at tennis.

The WTA may also use shot clocks in Premier-level tournaments in 20-19.