Johanna Konta has the focus to be Roland Garros champion – Billie Jean King

The British No 1 will play in the last four at a grand slam for the third time when she takes on Czech teenager Marketa Vondrousova on Friday.

Neither was expected to make it this far, but both have been in great form and, such is the unpredictability of the women’s game, it would not be a big surprise if any of the six players left in the draw went on to win the title.

Konta is obviously among those, and King sees no reason she cannot end the fortnight with the trophy.

“I think anyone can win in women’s tennis right now,” she said. “It’s such a toss-up. Every time we talk among ourselves, ‘Who’s going to win?’, it’s like, ‘We don’t know’. Whoever is playing well that week. And Konta is playing the best I’ve probably ever seen her play except for when she had that run at Wimbledon. But I think she’s actually better now.

“I think her concentration is better day in and day out. I feel like some days she gets like too hyped up and she seems to be very calm right now.

“I can tell she’s had a lot of therapy and I think it’s helped her. She’s quite clear now in her thoughts in what she wants to do and she just keeps improving. Because she wants to. You can tell she wants to keep improving.

“She’s really concentrating well and she’s hitting so big - her serve’s big, her ground strokes are big. She’s totally focused right now. She just has to stay on, stay the way she is.”

Konta’s match was postponed until Friday because of rain at Roland Garros.

No singles action was possible on Wednesday, meaning the quarter-finals that had been scheduled have now been delayed until Thursday.

To be fair to the women’s players in the top half of the draw, which includes defending champion Simona Halep, both semi-finals will now be played on Friday with the final on Saturday.

The finalist from the top half will have to play three days in a row while the winners of the men’s quarter-finals between top seed Novak Djokovic and Alexander Zverev and Dominic Thiem and Karen Khachanov will also have to play again on Friday.

Organisers had pushed back the intended start time on Wednesday from 2pm every half an hour until 4.30pm when they decided the forecast made any further attempts at getting under way futile.

Another headache for tournament organisers is that, although the forecast for Thursday is good, more rain is expected on Friday.