Novak Djokovic will play in January's Adelaide International, a year after being deported from Australia because of his Covid-19 vaccination status.
The Serb, who has won a record nine Australian Open titles, is also set to compete at the first Grand Slam of the year after his visa ban was overturned.
Britain's Andy Murray, Kyle Edmund and Jack Draper will also play in Adelaide, with the event beginning on 1 January.
The Australian Open starts 15 days later in Melbourne.
As well as world number five Djokovic, there will be three other top-10 men's players in Adelaide, with Felix Auger-Aliassime, Daniil Medvedev and Andrey Rublev also competing.