Coco Gauff served 21 double faults as she threw away a winning position in the semi-final of the Wuhan Open against Aryna Sabalenka.

The 20-year-old American was in imperious form during the opening exchanges, dropping just one game as she raced through the opening set and she led 4-2 in the second before her service collapsed.

After three double faults in the first set, Gauff made nine in the second and nine more in the third as Sabalenka won 1-6 6-4 6-4.

Her 21 double faults was the most by a player in a main draw match in 2024.

Top seed Sabalenka, who is a two-time winner of this event, will face fifth seed Zheng Qinwen of China in Sunday's final.

Gauff, who beat Sabalenka to win the 2023 US Open, took a 4-2 lead in the second set after an early break as she continued her form from the first set.

But Gauff's service game suddenly collapsed, allowing the Belarusian world number two to record successive breaks as she won four games in a row to take the second set.

Gauff's service game deteriorated further in the decider and the American's anger at failing to see out the match threatened to spill over.

Sabalenka, who has never lost in Wuhan, extended her winning run to seven games in a row by taking the first three games of the third set,

Gauff showed her resilience by winning four of the next five to level at 4-4.

But, after Sabalenka held her serve, Gauff double faulted on match point to hand the former world number one the win.

"Coco is an incredible player," said Sabalenka.

"We've had a lot of tough battles in the past. She's in great shape and I knew going into this match that it would be tough and that I would have to work really hard to get the win.

"A couple of mistakes from her and and I felt I probably still have chances."