Sam Stosur, who won the US Open in 2011, has accepted a wildcard invitation into the Hobart International.
The 35-year-old headlines the tournament for the first time in six years when the top seed, who debuted in 2004, exited in the semi-finals.
The return comes straight after Stosur was honoured with Tennis Australia's spirit of tennis award on Monday.
The top Queenslander was announced on Wednesday at the Hobart International launch as one of two Grand Slam champions in the WTA event in January along with Russian former world No.2 Svetlana Kuznetsova.
The pair will accompany a strong field with past Hobart winners Elise Mertens, of Belgium, and Alize Cornet, of France, in the draw.
Caroline Garcia, also of France, will join Stosur playing in Hobart as former world top-five players for January.
Mertens, who holds an unbeaten singles and doubles record at the Australian Open warm-up tournament, made history in 2018 becoming its first back-to-back singles champion after successfully defending the title she claimed as a qualifier.
The world No.17 will be the highest-ranked player to enter the only Tasmanian WTA tour event since 2011 when No.16 Marion Bartoli was the top seed.
The 24 year-old has since made the 2018 semi-finals of the Australian Open and the 2019 quarter-finals at the US Open, finishing the past two seasons ranked inside the world's top 20 players in both singles and doubles.
Cornet returns to Hobart for her seventh appearance after she was the tournament's top seed this year.
Kazak Elena Rybakina is the second highest-ranked player in the singles field.
The world No.36 has just completed a breakthrough 2019 season after a Launceston International win from No.169 in February ignited her first WTA tour title at the Bucharest Open.
Two-time Grand Slam champion Kuznetsova plans to make her second visit to Hobart but first for 16 years.
The 34-year-old has scored four top-10 wins in 2019, including defeating Ash Barty to reach the Cincinnati final.
Attracting multiple Grand-Slam winners in Hobart for a historic first occasion can only add more depth to the field, according to Hobart International tournament director Darren Sturgess.
"The quality of the Hobart International 2020 field is exciting for us and for the fans," Sturgess said.
"We are thrilled to have former champions Elise Mertens and Alize Cornet returning in 2020 and to have some of the world's best female athletes performing in Tasmania is something we're very proud to showcase to the local community.
"So securing four of the top 40-players along with a host of players, who have won Grand Slams in singles and doubles is a great result."