Dubai - Unseeded Daria Kasatkina upset Wimbledon champion Garbine Muguruza 3-6, 7-6 (13-11), 6-1 on Friday with a dramatic fightback in their semi-final at the Dubai Championships.
After dropping the opening set and falling a break behind in the second, the 20-year-old Russian turned the tables, leaving the world No 3 gasping and completely out of the deciding set.
Kasatkina saved nine of 12 break points and broke Muguruza five times in a thriller lasting for more than two and a half hours.
In the second set the unseeded Kasatkina saved three Muguruza match points before coming good on her fourth set point.
In the third, Kasatkina, ranked 24th and winner of the Charleston title last spring, rode her rising momentum as the fight drained out of Muguruza.
"I was just trying to fight for every ball because Garbine, she's playing unbelievable," Kasatkina said.
"She's very tough opponent. She's hitting so hard, playing so fast. I was just trying to do whatever I could.
"Before the match I was really, really tired. When you're going on court, adrenaline is coming.
"You start to run, blood start to run into your body, that's it. You're just focused on every ball. The tired is somewhere, going somewhere."
Muguruza had been aiming to become only the fifth player to reach both Doha (last weekend) and Dubai finals in the same season.
"My game was fine. I feel I really struggled physically because I've been playing so many matches in a row. Today was very physical," Muguruza said.
"At the third set I really noticed it because my legs were starting to get very fatigue. I think all the accumulation came up a little bit.
"I'm remaining positive, I managed to play a lot of matches, good ones, final and semifinal. I think it's a great two weeks."
Results from the WTA tournament in Dubai on Friday (x denotes seeding):
Daria Kasatkina (RUS) bt Garbine Muguruza (ESP x2) 3-6, 7-6 (13/11), 6-1
Elina Svitolina (UKR x1) bt Angelique Kerber (GER x6) 6-3, 6-3