Nick Kyrgios and Bernard Tomic will face off for the first time at this week's Kooyong Classic.
After accepting a late entry into the three-day event on Saturday, Kyrgios has been told he will play his one-time Davis Cup teammate and US Open doubles partner.
The event may be an exhibition with no rankings points up for grabs, but tournament director Peter Johnston has no doubts the former grand slam quarter-finalists will be taking their showdown seriously.
"For both guys it's their last competitive match before next week's Australian Open, so their focus will be on making sure their games are ready," Johnston said.
"At the same time it will be fun for the fans to watch it play out given they have never gone head to head before."
Kyrgios and Tomic were drawn to meet in the first round of last year's French Open in Paris, only for Kyrgios to withdraw with an elbow injury.
Both are desperate for court time ahead of the Open, with Kyrgios only playing two matches since injury prematurely ended his 2018 season in mid-October.
Ranked 14th in the world this time last year, the 2014 Australian Open quarter-finalist will tumble outside the top 50 on Monday after losing in the second round of last week's Brisbane International.
After taking time out from tennis and appearing on reality TV last March, Tomic regained his place in the top 100 with a solid season but opted against playing either of the sanctioned pre-Australian Open events in Brisbane and Sydney.
Tomic will also partner his sister Sara in mixed doubles at Kooyong, which also feaures dual grand slam finalist Kevin Anderson and 2018 Open runner-up Marin Cilic.
The event starts on Tuesday with organisers yet to release when Kyrgios and Tomic will clash.
