World number one Simona Halep crashed to a shock defeat to Kiki Bertens in a dramatic final of the Western & Southern Open.
Bertens prevailed 2-6 7-6 (8-6) 6-2 in a real test of nerve as she was forced to save championship point in a roller-coaster second set when the tables turned in thrilling fashion.
It was the biggest win of the world number 17’s career, the first time a Dutch player had won in Cincinnati and her maiden win against a world number one, taking two hours and five minutes to do it.
Halep was playing close to her best in a one-sided opening set that she claimed 6-2 in 30 minutes, her clinical tennis overwhelming the underdog.
The early stages of the second set produced an unexpected swing as Bertens exploded into life to establish a 4-1 lead, only to then crumble once more.
She won just two points en route to seeing the score tied at 4-4 and, as her lead ebbed away, so too did her stamina.
But the ninth game witnessed a stirring revival as she survived break point that arrived at the end of a monster rally before upping the power to take the game.
Set point came cloaked in luck as a return struck the net and slipped over, but Halep rallied to take the 10th as her opponent hurled her racket into the air in frustration.
Another swing came early in the tie-break as Bertens reeled off four points in a row to establish a 4-2 lead and, having later saved Championship point, she took the set.
And the decider was proving equally hard work for a visibly frustrated Halep, who lost 10 points in a row as she conceded a 4-1 lead and responded by shaking her head.
It was turning into a procession and Bertens took advantage of the Romanian’s loss of composure to close out the set.