Britain's Katie Boulter hopes to "keep getting better and better" as she prepares to face best friend Freya Christie in Friday's Progress Tour Women's Championships semi-finals.

The 23-year-old was ranked 82nd in the world last year before falling to 374th after time out with a back injury.

British number seven Burrage will play Alicia Barnett in the other semi-final.

"I'm not that match tight but I feel like I've done a really good job in my time off to keep myself prepared and hopefully it will keep getting better and better," Boulter told BBC Sport after her win against Burrage.

"[Freya Christie] is my best friend and I'm sure we'll both put everything out on the court and it will be a really good match."

The match against Burrage was Boulter's toughest test of the week so far and she had to fight back from a double break down at 0-3 in the second set. She failed to convert three match points when leading 5-4 as Burrage held firm to take it to a tie-break.

Boulter raced into a 5-1 lead in the tie-break but then wobbled again as she missed another two match points before finally converting her sixth.

While Burrage is the highest ranked player at the tournament after a series of withdrawals, Boulter has been the player to beat because of her pedigree as the former British number two and her Grand Slam singles main draw experience.

British number six Katie Swan also entered the domestic tournament at Roehampton's National Tennis Centre but withdrew on Tuesday with a right hip injury.

Heather Watson and Harriet Dart pulled out before the event with ankle and groin injuries respectively.

Players call their own lines and collect balls under coronavirus restrictions at the tournament. Aside from the Premier singles that features Boulter, there is also a doubles competition and a Division 1 singles event.