Petra Kvitova claimed her second victory of the weekend to seal the Czech Republic a place in the semi-finals of the Fed Cup.
However, the former Wimbledon champion had to recover from match point down to beat Sam Stosur and give the Czechs an unassailable 3-0 lead over Australia in Ostrava.
Kvitova was on court for two hours and five minutes in posting a 2-6 7-6 (7/3) 6-4 victory on the hard court.
In a match containing 13 service breaks, the world No 9 Aussie held match point at 5-4 40-30 on Kvitova's serve in the second set before losing a tie-break and eventually the match.
The visitors have paid a heavy price in the contest losing all four sets that went to a tie-break.
The holders, for whom Lucie Safarova is also playing singles for the hosts, are chasing a third successive win in women's tennis premier team event and they will take on Italy in the semi-finals.
Italy wrapped up a 3-2 victory over the United States when Sara Errani and Roberta Vinci defeated Liezel Huber and Varvara Lepchenko 6-2 6-2 in the deciding doubles rubber.
Slovakia will play Russia in the other semi-final after Daniela Hantuchova beat Vesna Dolonc 6-3 6-2 to claim her second victory of the match and give the Slovaks a 3-1 win over Serbia.
Jana Cepelova had earlier secured a 5-7 7-5 11-9 success over Serbia's Bojana Jovanovski, who battled bravely for over three hours despite struggling with a back injury.
Elena Vesnina and Ekaterina Makarova sent Russia through when they secured a 6-2 6-2 win over Japan's Ayumi Morita and Misaki Doi for a 3-2 victory.