Alicia Barnett wins match in Billie Jean King Trophy

Great Britain captain Anne Keothavong was left pinching herself in disbelief after watching her players pull off a remarkable 3-0 victory over the five-time champions in Glasgow to reach the semi-finals of the Billie Jean King Cup for the first time in 41 years.

Team GB knew that after a defeat by Kazakhstan on Tuesday only a whitewash against Spain

Britain went into the tie at the Emirates Arena with seemingly little chance.

But Heather Watson and Harriet Dart overcame much higher ranked opponents – the latter in tears after stunning 13th-ranked Paula Badosa – and former Stroud High School pupil Alicia Barnett and playing partner Olivia Nicholls shrugged off the pressure of a winner-takes-all doubles rubber to defeat Aliona Bolsova and Rebeka Masarova.

The pair were late call-ups following Emma Raducanu’s withdrawal and had not been in anything remotely like this situation before but again played superbly to clinch a 7-6 (5) 6-2 victory.

“It was just wonderful to see everything unfold today,” said captain Keothavong.

“I still can’t believe it. To beat Spain without dropping a set.

"But knowing that we had to win 3-0, and then the girls just smashing it by not dropping a set, it was just unreal.”

Alicia Barnett and Olivia Nicholls only made their debut in the competition on Tuesday after earning a late call-up and impressed hugely in victory over Elena Rybakina and Anna Danilina.

Barnett told the BBC: "It's pure passion out there.

"These girls are playing for each other, we've had so much fun.

"There have been rippers out there."

Britain last reached the semi-finals back in 1981, when Sue Barker and Virginia Wade carried them to the last of four finals in what was then known as Fed Cup, and have been in the competition’s doldrums for much of the intervening time, with this sort of result so far off their radar it was not even a dream.

They now move through to a semi-final clash against Australia, where they should legitimately feel they have a strong chance of victory.

“The sky’s the limit after what we have shown so far,” said Nicholls.

"We were definitely underdogs in this group.

"No doubt about it."

Spain captain Anabel Medina Garrigues was full of praise for the British performances, saying: “Great Britain today played an unbelievable tie.

“Four players played unbelievable.

"The only thing we can say is well done, good job, and good luck in the semi-finals.”

Australia became the first team to book their place in the last four with a 3-0 victory over Belgium.