Unseeded Marketa Vondrousova beat fourth seed Jessica Pegula in a topsy-turvy match to reach the Wimbledon semi-finals on Tuesday.

The Czech player, ranked 42 in the world, clawed her way back from 4-1 down in the deciding set to win 6-4, 2-6, 6-4.

Pegula was quickly out of the blocks, breaking the former French Open finalist at her first opportunity but that proved a false dawn as she lost three service games in the first set, landing just 41 percent of her first serves.

The American, 29, found more rhythm on her serve in the second set and cut her error count, surging into a 4-1 lead and sealing the set with her second break.

Pegula was in total charge when she broke again in the fourth game of the decider to lead 3-1 before the match was suspended for the roof to be closed due to rain at the All England Club.

She held serve when play resumed to take a 4-1 lead but the 24-year-old Czech, who had never previously never been beyond the second round at Wimbledon, dug deep to pull level.

Pegula faced a real struggle on her serve in the following game and sprayed a forehand long to hand Vondrousova a vital break and she took full advantage.

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