Johanna Konta overcame a nervous finish to knock out two-time former champion Petra Kvitova and reach the quarter-finals of Wimbledon for the second time.
The British number one weathered an early storm in a battle of fierce hitting from both players and was on the verge of victory at 5-1 in the final set.
Kvitova fought back with a run of three games in a row, saving two match points, but Konta served it out at the second time of asking to win 4-6 6-2 6-4.
Coupled with her third-round upset of Sloane Stephens, the 19th seed is positioning herself as a real contender for the title, and she will be a strong favourite when she takes on another Czech, unseeded Barbora Strycova, in the last eight on Tuesday.
There had been major doubts about Kvitova's fitness prior to the tournament, with the 29-year-old not having played a match since before the French Open because of a left forearm problem.
She had barely even been able to practise but, having won all of her first three matches in straight sets, it seemed fair to assess that Kvitova was feeling close to 100 per cent.
It certainly looked that way in the early stages as she thumped winner after winner – 11 in the first five games alone. But Konta is a talented ball striker, too, and she stayed with her opponent very well.
In fact it was Konta who had the first openings but, from 4-4 15-40, Kvitova sent down four strong serves to avert the danger.That left Konta serving to stay in the set, and she could not manage it. She was unfortunate with a net cord that dribbled over but strong play from Kvitova took her to set point, and the home favourite dragged a forehand wide.
But the 28-year-old had come from a set down to beat Stephens and she made the perfect start to the second with a first break of the Kvitova serve.
The key moments came in the next game on Konta's serve, which she finally held after saving two break points.
Kvitova, who had been so assured, was now making an increasingly number of errors and Konta took full advantage to open up a 4-0 lead.
She missed a set point at 5-1 and then took a medical time-out to have strapping applied to her left ankle, but she did not seem concerned by the problem and served out the set with an ace.
Kvitova had won three of their four previous meetings, with Konta's only victory coming in Eastbourne in 2016, but it was the Brit who had the momentum and she struck a series of fierce backhands to break for a 2-1 lead in the decider.
The final one was called out, then shown to be in via HawkEye, and Konta gave umpire Kader Nouni no time to consider replaying the point, striding to her chair.
Konta looked supremely confident, and no wonder given she had won 13 of her last 14 matches that had gone to a deciding set.
A run of five successive games took her to the brink of victory but, serving for the match at 5-2, things became complicated. Two match points came and went and Kvitova retrieved one of the breaks.
When Konta stepped up to serve for the match again, the air of tension around Centre Court was palpable, but this time she made no mistake.
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