'Never seen that': Ash Barty in bizarre incident at Madrid Open

Ash Barty has extended her incredible winning streak to storm into the semi-finals at the Madrid Open, but not before a strange incident in which she lost a ball in the sun.

The World No.1, seeking back-to-back titles on clay following her triumph in Stuttgart, prevailed 6-1 3-6 6-3 in a compelling one hour 48 minutes tussle with old rival Petra Kvitova on Wednesday.

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In her 10th match against the double Wimbledon champion, Barty was able to level their head-to-head record at 5-5.

But Barty didn't have it all her way, with Kvitova sending the match to a deciding set in a typically tight tussle.

And not only did the Aussie star have to deal with her Czech opponent, she also had to battle the sun at times.

The World No.1 reckoned she had been looking forward to at last soaking up a few rays on the 'Caja Magica' court - and the weather duly obliged as the roof was opened on Wednesday.

But the sun played havoc with Barty late in the first set when she completely lost sight of a ball while attempting an overhead smash.

In extraordinary scenes, Barty simply turned away from the ball and let it bounce twice - handing Kvitova the point.

"Oh my, that's extraordinary," one TV commentator said.

Fans were also left rather stunned by the bizarre moment.

Ash Barty seeking revenge over Paula Badosa

It wasn't quite the vintage Barty who outplayed French Open champ Iga Swiatek in the previous round but her 6-3 1-6 6-3 quarter-final win again showcased a player who's seemingly forgotten how to lose as she came up trumps again when it mattered most.

She played her best tennis in the third set, as she's done so often this year when winning 11 of her 12 matches that have gone to a final-set decider - and for that, she reckoned, she could thank Kvitova, with whom she savoured every minute of their 10th engrossing battle.

"Actually, Petra and I said at the start of the match, 'it's a beautiful day, sun's shining, like, let's go and play, let's enjoy it'," smiled Barty.

"Any time you get to play clay-court tennis out in the sun, I feel like it adds a different element; the court can become quite bouncy and quick and the conditions can change dramatically - but it was certainly nice to get a bit of a tan today.

"Petra and I, we respect each other as tennis players, and I respect her immensely as a person. I love who she is as a person, and on the court it's more than just about the result.

"We love to compete, we love to test each other, we love to test ourselves. Being able to enjoy it and have a smile on your face is a massive part why I feel the tennis is always a really good level."

Next up for Barty in Thursday's last-four clash is a chance for revenge against Spanish wildcard Paul Badosa, who's one of only three women to beat her this year - in Charleston last month on the green clay when the Australian looked distinctly weary coming off her triumph in Miami.

"Ash, what can I say? I played her in Charleston. Now she knows me. No.1 in the world, they don't like to make mistakes two times in a row, so for sure I expect a tough match and completely different to Charleston," said world No.62 Badosa.

with AAP

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