Prague - Petra Kvitova led holders Czech Republic into the Fed Cup semi-finals by giving them a winning lead with a three-set victory over Australia's Samantha Stosur in Ostrava on Sunday.
The Czechs also won the dead doubles rubber later on Sunday for an overall 4-0 win.
In the clash of the teams' number-one players, Kvitova, the world No.8, needed two hours and five minutes to beat 9th-ranked Stosur 2-6, 7-6 (7/3), 6-4.
On the hardcourt in Ostrava, about 320 kilometres (200 miles) east of Prague, Stosur took the first set easily, then had a match point in the second, but Kvitova fought back to take the set in a tie-break.
In the decisive set, she gave up a break leading 5-3 but immediately took it back to give the Czechs a seventh straight Fed Cup win.
"I'm really happy. I think it was one of my best games this season," said Kvitova, who led the Czechs to two straight Fed Cup victories in 2011 and 2012.
"We won, but it wasn't easy, each game was like a seesaw," she added.
Stosur said she was also happy with the way she played despite the loss.
"I really don't think I did much wrong today, I think Petra played a very good match," Stosur, the 2011 US Open champion, told the fedcup.com website.
"We both played very high quality and when it comes down to that it's just a point here and a point there," she added.
On Saturday, Kvitova beat Australia's Jarmila Gajdosova 7-6 (7/2), 6-3, before Lucie Safarova handed the Czechs a second point against Stosur in two tie-breaks - 7-6 (8/6), 7-6 (7/4).
In Sunday's dead doubles rubber, Czechs Andrea Hlavackova and Lucie Hradecka, the world numbers three and four in the format, beat Australian Open finalists Casey Dellacqua and 16-year-old Ashleigh Barty 6-0, 7-6.
The Czechs are eyeing a Fed Cup treble, something the former Czechoslovakia - which split into the Czech Republic and Slovakia in 1993 - achieved in 1983-1985.
In the semi-finals, the Czechs will face either Italy or the United States. The US team led hosts Italy 2-1 on Sunday afternoon.
Kvitova said she would prefer Italy in the semi-finals as "it would be much better than having to fly to America, although they would be terribly strong on clay."
Fed Cup World Group I first round results this weekend:
World Group I
At Ostrava
Czech Republic 4 Australia 0
Saturday
Petra Kvitova (CZE) bt Jarmila Gajdosova (AUS) 7-6 (7/2), 6-3
Lucie Safarova (CZE) bt Samantha Stosur (AUS) 7-6 (8/6), 7-6 (7/4)
Sunday
Petra Kvitova (CZE) bt Samantha Stosur (AUS) 2-6, 7-6 (7-3), 6-4
Andrea Hlavackova/Lucie Hradecka (CZE) bt Ashleigh Barty/Casey Dellacqua (AUS) 6-0, 7-6 (7/1)
Note: Fifth rubber not played
At Rimini
Italy 3 USA 2
Saturday
Sara Errani (ITA) bt Jamie Hampton (USA) 6-2, 6-1
Varvara Lepchenko (USA) bt Roberta Vinci (ITA) 2-6, 6-4, 7-5
Sunday
Varvara Lepchenko (USA) bt Sara Errani (ITA) 7-5, 6-2
Roberta Vinci (ITA) bt Jamie Hampton (USA) 6-2, 4-6, 6-1
Sara Errani/Roberta Vinci (ITA) bt Liezel Huber/Varvara Lepchenko (USA) 6-2, 6-2
At Moscow
Russia 3 Japan 2
Saturday
Maria Kirilenko (RUS) bt Kimiko Date-Krumm (JPN) 7-6 (7/3), 6-4
Ayumi Morita (JPN) bt Ekaterina Makarova (RUS) 6-2, 6-2
Sunday
Ayumi Morita (JPN) bt Elena Vesnina (RUS) 6-4, 6-1
Ekaterina Makarova (RUS) bt Kimiko Date-Krumm (JPN) 6-1, 6-1
Elena Vesnina/Ekaterina Makarova (RUS) bt Ayumi Morita/Misaki Doi (JPN) 6-2, 6-2
At Nis
Serbia 2 Slovakia 3
Saturday
Daniela Hantuchova (SVK) bt Bojana Jovanovski (SRB) 7-5, 6-2
Vesna Dolonc (SRB) bt Dominika Cibulkova (SVK) 4-6, 4-5 - retired
Sunday
Jana Cepelova (SVK) bt Bojana Jovanovski (SRB) 5-7, 7-5, 11-9
Daniela Hantuchova (SVK) bt Vesna Dolonc (SRB) 6-3, 6-2
Vesna Dolonc/Aleksandra Krunic (SRB) bt Magdalena Rybarikova/Jana Cepelova (SVK) - walkover
World Group II
At Berne
Switzerland 4 Belgium 1
Saturday
Yanina Wickmayer (BEL) bt Stefanie Voegele (SUI) 6-1, 4-6, 8-6
Romina Oprandi (SUI) bt Kirsten Flipkens (BEL) 6-3, 6-3
Sunday
Romina Oprandi (SUI) bt Yanina Wickmayer (BEL) 6-2, 6-2
Stefanie Voegele (SUI) bt Kirsten Flipkens (BEL) 6-2, 7-6 (7/4)
Timea Bacsinszky/Amra Sadikovic (SUI) bt Ysaline Bonaventure/Alison van Uytvanck (BEL) 6-4, 6-4
At Buenos Aires
Argentina 2 Sweden 2
Saturday
Paula Ormaechea (ARG) bt Johanna Larsson (SWE) 6-3, 6-0
Florencia Molinero (ARG) bt Sofia Arvidsson (SWE) 6-3, 2-6, 6-1
Sunday
Sofia Arvidsson (SWE) bt Paula Ormaechea (ARG) 7-5, 6-7 (6/8), 3-2 - retired
Johanna Larsson (SWE) bt Florencia Molinero (ARG) 6-3, 6-2
Mailen Auroux/Maria Irigoyen (ARG) v Sofia Arvidsson/Johanna Larsson (SWE)
At Alicante
Spain 3 Ukraine 1
Lourdes Dominguez Lino (ESP) bt Elina Svitolina (UKR) 5-7, 6-2, 8-6
Silvia Soler-Espinosa (ESP) bt Lesia Tsurenko (UKR) 7-5, 6-4
Sunday
Maria-Teresa Toro-Flor (ESP) bt Yuliya Beygelzimer (UKR) 6-4, 6-2
Yuliya Beygelzimer/Olga Savchuk (UKR) bt Nuria Llagostera Vives/Maria-Teresa Toro-Flor (ESP) 6-3, 2-6, 10-5
Note: Fifth rubber not played
At Limoges
France 1 Germany 3
Sabine Lisicki (GER) bt Pauline Parmentier (FRA) 7-5, 7-5
Julia Goerges (GER) bt Kristina Mladenovic (FRA) 6-3, 7-6 (7/5)
Sunday
Julia Goerges (GER) bt Pauline Parmentier (FRA) 6-4, 6-2
Alize Cornet/Kristina Mladenovic (FRA) bt Anika Beck/Anna Lena Groenefeld (GER) 6-3, 6-4
Note: Fifth rubber not played