Iga Swiatek joked "in 20 minutes, I'll be dead" after securing back-to-back wins that booked Poland's place in the Billie Jean King Cup semi-finals.

The Poles are through to the last four of the competition for the first time, having come from behind to beat the Czech Republic 2-1.

After Marie Bouzkova defeated Magdalena Frech in the opening singles match, Swiatek pulled Poland level by edging out Linda Noskova 7-6 (7-4) 4-6 7-5 after two hours and 39 minutes.

The five-time major winner returned to court just half an hour later for the doubles decider - and her first in this event since 2019.

Nevertheless, Swiatek was not to be denied, partnering Katarzyna Kawa to a 6-1 6-4 win over Bouzkova and Katerina Siniakova.

"It was an exhausting day, but everything worked," the world number two said. "We did a great job, we won."

Iga Swiatek levelled the score for Poland against Czechia, keeping their hopes of reaching the semi-final of the Billie Jean King Cup alive.

The world number two had to dig deep for the win though, triumphing 7-6 (7-4) 4-6 7-5 in two hours and 41 minutes in the second of Poland's singles matches on Saturday.

In their earlier match, Marie Bouzkova had put Czechia ahead but also had to go the distance to beat Magdalena Frech.

It means their quarter-final tie will be decided by doubles, which Swiatek will also play – her first doubles match at the Billie Jean King Cup since 2019 – as they aim to try and win the title for the first time.

The winner of that tie will face Italy in the semi-final, with Jasmine Paolini leading them into the final four.

Japan had taken the lead in the best-of-three tie thanks to Ena Shibahara's win over Elisabetta Cocciaretto, but the French Open and Wimbledon runner-up turned things around.

She beat Moyuka Uchijima 6-3 6-4 in straight sets to level the tie before pairing up with Sara Errani, three months after their Olympic gold triumph, to complete the comeback.

Italy has won the competition four times previously but are looking to better last year's result when they fell to Canada in the final.

Iga Swiatek and Emma Raducanu were both victorious as Poland and Great Britain won their first-round ties at the Billie Jean King Cup Finals on Friday.

Poland won both of their singles matches against Spain in Malaga, while Britain did likewise versus Germany to seal their own spot in the competition's last eight. 

World number two Swiatek clinched Poland's progress with a 6-3 6-7 (6-8) 6-1 victory over Paula Badosa, after Magda Linette had put them ahead by beating Sara Sorribes Tormo in a gruelling three-hour, 51-minute affair.

Speaking after her own win, Swiatek hailed the endurance of team-mate Linette, who triumphed 7-6 (8-6) 2-6 6-4.

"I wouldn't say that I pushed us to the quarter-finals, because Magda pushed us to the quarter-finals, so we did it together," the five-time grand slam champion said.

"I'm glad that we won a match as Team Poland. I felt like it was my best match since the US Open. I knew that I could come back in the third set and try to win it for Poland."

Later on Friday, Great Britain were propelled to victory by Raducanu and Katie Boulter, both of whom were straight-sets victors.

Raducanu, playing her first match in almost two months after recovering from a foot injury, beat Jule Niemeier 6-4 6-4.

The 2021 US Open champion started well and her effective serve was a key feature of the opening set, though she later required six match points to get over the line as Niemeier refused to go down without a fight.

Britain will face defending champions Canada in the last eight after Boulter raced to an impressive 6-1 6-2 victory over Laura Siegemund, ensuring there was no need for Olivia Nicholls and Heather Watson to team up for a deciding doubles match.

Barbados’ women’s tennis team made history on Saturday by advancing to Americas Group II of the Billie Jean King Cup at the National Racquet Centre in Tacarigua, Trinidad & Tobago.

The Bajans first went 4-0 in Pool A preliminary round action with wins over Antigua & Barbuda (3-0), Jamaica (2-1), Bahamas (3-0) and Trinidad & Tobago (2-1) from August 5-8 before coming up against El Salvador in the promotional playoff on Saturday.

El Salvador advanced to that playoff thanks to a second-place finish in Pool B after three wins and one loss.

In the first match of Saturday’s playoff, El Salvador’s Michelle Irigoyen secured a dominant 6-0, 6-2 victory over Barbados’ Serena Bryan before Gabrielle Leslie tied proceedings at 1-1 with a 6-1, 6-2 victory over Sara Valentina Cruz Bonilla.

The deciding doubles match was a fitting way to determine the victor as both teams left it all on the court.

Barbados’ Hannah Chambers and Cherise Slocombe went up against El Salvador’s Bonilla and Irigoyen.

Chambers and Slocombe took the first set 6-3 before the El Salvador pair roared back into it with a bagel (6-0) in the second set.

The teams then played out a marathon third and deciding set which Barbados eventually won 11-9 to book their spot in Americas Group II.

Costa Rica will join them in Group II after beating Jamaica 2-1 in the other playoff.