British number one Johanna Konta is hoping for more of the home-crowd energy that pulled her back from the brink of exhaustion in their last tie when GB seek Fed Cup promotion this weekend.

Britain face Kazakhstan in a best-of-five play-off at London's Copper Box Arena, with Konta and her team-mates hoping to end a 26-year wait for promotion to Fed Cup World Group II.

It is the fifth time in eight years Britain have reached the play-offs and every previous tie has been away from home, with defeats keeping them in the third tier of women's team tennis.

This year they earned their place with victory in February's round-robin event in Bath, where Konta battled fatigue and needed to be helped to her feet at the end of her match in the decisive win against Serbia.

"The home support lends you energy when you need it," Konta, 27, told BBC Sport.

"You really feed off their emotions and their desires for you. It is also the team you have behind you."

Konta's world ranking has dropped from 23 to 46 in the past 12 months but she made changes to her coaching team in November and reaped the rewards with a determined performance in Bath.

"Overall, I feel good about the work I am putting in with my own team," she said. "I am enjoying my tennis and enjoying my life so it's a good position to be in."

Who is playing and what is the format?

GB captain Anne Keothavong has named the country's top five players in her team, with Konta and British number two Katie Boulter expected to feature in the singles.

There are two singles rubbers on Saturday (from 13:30 BST), with two reverse singles and a doubles match on Sunday (from 12:00).

If the tie is settled after three singles matches, the fourth singles is not played but the dead doubles rubber is. If the tie is settled after four singles, the dead doubles is also still played.

The teams are relatively evenly matched on paper with Kazakhstan led by world number 38 Yuliya Putintseva and Zarina Diyas, who is ranked 107th.

But Britain have a greater depth to their squad, with Heather Watson, Harriet Dart and Katie Swan all ranked in the top 200.

Kazakhstan, meanwhile, have named only four players, picking world number 372 Anna Danilina and doubles player Galina Voskoboeva in addition to Putintseva and Diyas.

A revamped Fed Cup Finals - featuring 12 teams - could be up and running as early as next April.

A win against Kazakhstan would almost certainly guarantee Britain's involvement in this new format.

GB 'not talking about' past heartbreak

This is the third consecutive year Great Britain have reached this stage, with last year's efforts ending in a heartbreaking 3-2 defeat by Japan after Konta and Watson had been a set up in the deciding doubles match.

"I'm sure eventually we will take our chance. We will give it our best," said Watson.

"We don't talk much about the past. We just talk about the future."

Watson, overtaken by Boulter as British number two earlier this year, will also want to put behind her the disappointment of missing February's Europe/Africa Zone round-robin event with flu.

"I was the most ill I've been in my life. It was dreadful," she said. "I had a temperature, I was vomiting, I was coughing - I even damaged a rib from coughing too much.

"I was there but I was bed-bound the whole time. I just hoped that each day I could get better so I could go and even just support. It was a shame because I have played in the Fed Cup for so many years and this was the first time it was at home. I was really sad to miss it.

"I will at least be courtside this time around and will hopefully get to play because that would be really special to play at home."

'I live for the big moments' - Boulter

Boulter enjoyed a dream Fed Cup singles debut in Bath, winning all of her rubbers in a performance Konta described as "exceptional".

The 22-year-old now has her sights on improving her ranking and one day becoming British number one.

"It is great to have that healthy competition within the team," she told BBC Sport. "We are all fighting for that place and that chance to show that we are working hard to do the best that we can. It's good for Jo and it's good for Heather and all the other girls coming up."

Boulter says she was not fazed by the pressure of playing the opening match in every tie in Bath and wants to do the same in London.

"I am somebody who likes to get the crowd going and show emotion. I live for the big moments," she said. "Hopefully I can get a lot of support. It's a good start for everybody and it worked well in Bath so hopefully we can keep the winning formula."

'Team can be strong role models'

With former men's world number one Andy Murray's retirement imminent, there will be a big gap to fill in British tennis.

And Keothavong believes there is an opportunity for her players to become strong role models like the three-time Grand Slam champion.

"The players we have on the Fed Cup team deserve the attention they get and more," she said. "They are not Grand Slam champions yet, like Andy, but there is lots of potential.

"There is the appetite for women's tennis and it's important we have strong role models in this country. Every member of the Fed Cup team can be a strong role model for any young tennis player aspiring to do what they are doing."

She also hopes playing a tie in her native east London, which has never hosted a Fed Cup or Davis Cup tie, will open up the sport to a new audience.

Konta agreed, adding: "We are all really looking forward to the fact we are playing at home again. We have not had to travel across the world at this time of the year, which is a new experience for us.

"It really does help you in tough situations."

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