The top seeds advance Team Greece wins the City Final in Perth, setting up a semifinal showdown with Italy in Sydney.
World No.4 Stefanos Tsitsipas has produced the goods in the singles and doubles to power Greece into the semi-finals of the United Cup alongside the US, Poland and Italy.
Tsitsipas defeated Borna Coric in three sets earlier on Wednesday in the Perth city final, but the star Greek was forced to return for the mixed doubles late at night after Croatia levelled the tie at 2-2.
Maria Sakkari and Tsitsipas then teamed up to win the mixed doubles 7-6 (8-6) 6-4 against Petra Martic and Borna Gojo to seal the tie and a spot in the semi-finals, which start in Sydney on Friday.
Greece will take on lucky losers Italy, while the US face Poland in the other semi.Italy lost 3-2 to Poland in the Brisbane city final, but earned a spot in the semis given they had the best record of the losing teams.
In Perth, Tsistipas avoided a nasty case of deja vu to score a win in the first men's singles rubber.The favourite was in complete control before Borna Coric launched a brave fightback, saving two match points in the second set and five in total before finally falling 6-0 6-7 (4-7) 7-5 .Coric had saved six match points on his way to beating Tsitsipas at the 2020 US Open and looked on track for a repeat when he twice had breaks in the deciding set.Tsitsipas, mistake-free in the first set, cast aside the disappointment of three more missed match points at 6-5 to finally take the crucial point for Greece.