World No 2 Iga Swiatek defeated Paula Badosa 6-3, 6-7 (5/7), 6-1 to take Poland into the Billie Jean King Cup quarterfinals on Friday with a 2-0 victory over hosts Spain.
Magda Linette put Poland ahead in the tie with a hard-fought 7-6 (8/6), 2-6, 6-4 marathon victory in three hours 51 minutes against Sara Sorribes Tormo.
Poland matched their best ever BJK Cup result by reaching the last eight for the first time since 2015, where they will face 11-time champions Czech Republic.
Friday's tie had been postponed on Wednesday after a severe weather alert in the region, following devastating floods in the east of Spain.
Five-time Grand Slam champion Swiatek, appearing in the BJK Cup finals for the first time, was given a stern test by world number 12 Badosa, but eventually triumphed by converting her fourth match point.
Iga takes the match and the tie for @pzt_tenis 🇵🇱
— Billie Jean King Cup (@BJKCup) November 15, 2024
A dominant 3rd set from Swiatek see's her win 6-3 6-7(7) 6-1 👏#BJKCup pic.twitter.com/TWclSye0uy
"Magda played an amazing match in the morning, we both did it... I'm happy we finally won a match in the Billie Jean King Cup finals, it's a huge step for sure," said Swiatek.
"For sure (Badosa) pushed me and there was a lot of pressure."
The first match was even closer with Linette emerging triumphant after a gruelling scrap against world number 106 Sorribes Tormo at the Martin Carpena arena.
The Pole defeated her opponent for the first time in five meetings with their tussle finishing nine minutes short of the longest ever BJK Cup match.
"I hate playing Sara... I knew it was going to take me four hours and it did," said Linette, ranked 38th.
"I'm so happy, I've never beaten her before and it took everything that I had today."
On Thursday Slovakia upset the United States and finals debutants Japan squeezed past Romania to reach the quarterfinals.