Ash Barty and John Peers have reached the final four of the Olympic mixed doubles, thriving in the deciding match tiebreak to beat the Stefano Tsitsipas-powered Greece 6-4 4-6 10-6.

The Australians lifted in the deciding first-to-10 tiebreak after a scrappy match from both teams, world No.4 Tsitsipas and No.19 Maria Sakkari ruing costly errors that led to the decisive break of serve in the first set.

Tsitsipas came from 0-30 on serve to close out the second set, but Australia shone in the match tiebreak, a reflex volley from doubles specialist Peers the catalyst as they went from 2-2 to an 8-4 lead.

Fresh off her Wimbledon title, world No.1 Barty had endured a forgettable Tokyo campaign when she lost her first-round singles match and then a tight women’s doubles quarter-final with Storm Sanders on Wednesday.

Australians @ashbarty and @johnwpeers are into the mixed doubles semifinals and one win away from playing for an Olympic gold medal 🏅 #GoAussies #TokyoTogether | #Tokyo2020 | #Tennis | @AUSOlympicTeamhttps://t.co/vYsnrAHpM2

— TennisAustralia (@TennisAustralia) July 29, 2021

But it could be third time lucky in her pursuit of Olympic gold, alongside long-time friend and doubles specialist Peers.

They will play Russian duo Anastasia Pavlyuchenkova and Andrey Rublev for a spot in the gold medal match, while a loss will see them fighting for bronze.

Peers and Barty have long been friends, playing together before Barty took a break from tennis and then even living with the Peers family when she returned to the sport in 2016.

“For Johnny and I this is a really, really special moment to make Mama Peers proud,” Barty said before their campaign on Wednesday.

-AAP