Great Britain find themselves locked in a real battle with unfancied Sweden at London’s Olympic Park. Needing a win to maintain their status among the world’s elite nations, they ended the first day with the score tied at 1-1.

This was not the position that British captain Anne Keothavong would have wanted to be in overnight. The Swedish team looked underpowered on paper, after injuries ruled out both of their strongest players and left them without anyone ranked inside the world’s top 300. Any logical prediction would have expected the home team to win both the opening rubbers.

But these team competitions are strange beasts. Upsets come around much more regularly than in regular tour events. In this instance, it was world No 372 Kajsa Rinaldo Persson who delivered one.

Rinaldo Persson opened this Billie Jean King Cup play-off against the second-string Brit Jodie Burrage, and was 4-0 down within moments. At that stage, Keothavong could have been forgiven for switching off and browsing her social-media feed, so easy did the going look.

Suddenly, though, Burrage lost her timing and her poise, while her opponent started retrieving balls from unlikely positions. Almost before the fans knew what was happening, 4-0 for Great Britain had become 4-6. And a mentally shattered Burrage then gave up the second set as well, by a 6-1 scoreline.

‘That type of pressure – I have never understood it’

Afterwards, Burrage admitted that the occasion had become too much for her. “I think it’s just so different when you’re playing for yourself and then when you’re playing for a team,” she said. “That type of pressure – I have never really understood it before.

“I’m hurting for other people,” she added. “That’s why I’m p----- off with myself, even more than I’ve ever been after any of my matches.”

Great Britain now needed their most reliable performer, Katie Boulter, to restore some equilibrium to a dangerously listing ship. As well as having the best ranking (No 58) in this tie by some distance, Boulter has built up significant experience in the BJK Cup, with nine previous match wins to her name over singles and doubles.

As it turned out, Boulter’s extra firepower was far too hot for Sweden’s other pick – world No 532 Caijsa Hennemann – to handle. She reeled off 18 clean forehand winners in a 6-2, 6-1 victory that felt like a training exercise, and sent the 5,500 capacity crowd away from the Copper Box with their spirits restored.

Big call for Keothavong to make

There is a tricky call now for Keothavong to make. Should she turn to Harriet Dart, or even Heather Watson, to face Hennemann in Sunday’s first match? Or should she stick with Burrage and hope that she will learn from Saturday’s chastening experience?

“Jodie knows that we’re all disappointed for her, given that that was her debut in the competition,” said Keothavong. “You want it to be a positive experience, and that was unfortunate. There will be a discussion [about selection], but you wouldn’t expect me to say anything about that here.”

Burrage declared herself ready to return, saying “100 per cent I would like another go. But that’s going to be Anne’s decision at the end of the day.”

The Swedish captain, Johanna Larsson, is a veteran of 48 BJK Cup ties as a player. She cannily pointed out that “The Brits still have the pressure on them.” Which, as Keothavong acknowledged later, was exactly what one would expect Larsson to say.

Boulter also admitted the truth of the remark when she passed through the interview room. “They [the Swedes] are gonna have a swing,” Boulter said. “They’ve got no pressure at all. But we are going to fight our little hearts out.”