Aryna Sabalenka’s defence of her Madrid Open title ended in a stunning defeat by American Hailey Baptiste in the quarter-finals.

Baptiste saved six match points in the third set to come through 2-6 6-2 7-6(8-6) in just over two and a half hours, becoming just the second player this season – after Elena Rybakina in the Australian Open final – to down the world No 1.

It brought an end to a 15-match winning streak for the Belarusian, who had overcome Baptiste easily in their only previous meeting, 6-4 6-4 in the Miami Open quarter-finals last month.

Baptiste said: “I played her a few weeks ago and it was a close match. I had a better idea of how to play her and adjustments I needed to make.

“It was an uncomfortable situation for her, me serving and volleying, hitting a drop shot in one of the match points. It's not the easiest position to put her in, which is the plan.”

It was the biggest win of the 24-year-old’s career and her first over a top-five player, while it also marked the first time Sabalenka had been beaten from match points up since the thrilling 2024 final in Madrid, won by Iga Swiatek.

Baptiste will face another top 10 player, world No 8 Mirra Andreeva, in her first WTA 1000 semi-final. The Russian won their only previous meeting 6-1 6-3 at Wimbledon last season.

“Somebody else that I played before and lost to,” Baptiste said. “A little bit of a revenge tour, I guess. I’m looking to go out there and play my game again and get another win.”

Sabalenka rolled through the first set easily but Baptiste fought back in the second, with back-to-back double faults from the Belarusian handing over a break in the opening game.

The American 30th seed was soon 4-0 up and although Sabalenka saved another break point and broke back, Baptiste was undaunted, firing down two forehand winners to break again and then take the match to a decider.

The third set was similarly topsy-turvy, with the top seed breaking for 5-4 – but Baptiste saved five match points in one service mammoth game, with an ace, serve and volley and drop shot lob all getting her out of trouble.

She ultimately broke the Belarusian for a third time in the set, only for Sabalenka to force a tie-break. She held a sixth match point at 6-5 in the tiebreak but Baptiste won three straight points to complete the biggest shock of the tournament so far and book a place in the Madrid last four for the first time.

Sabalenka said in her post-match press conference: “I feel like in Miami I didn't give her many opportunities. She couldn't break my serve. Here, the first game, second set, I just double-faulted twice out of nowhere. It felt like that gave her belief. After that, she just started playing more aggressively. She was playing brave tennis. What can I say? Well done.”