French Open champion Iga Swiatek has edged closer to a second grand slam title after setting up an Australian Open semi-final with American Danielle Collins.
Swiatek clawed her way to an epic 4-6 7-6 (7-2) 6-3 win over Kaia Kanepi, consigning the 36-year-old Estonian to a seventh defeat in major quarter-finals.
"This match was crazy and without the energy of the stadium it would have been hard to win," Swiatek said.
"In my match against Sorana (Cirstea) they (my team) told me that they believe I'm going win even though I lost the first set so I remembered that today."
Still only 20, Swiatek was a shock winner at Roland Garros in 2020 but has continued her rise through the rankings and entered the Open as the seventh seed.
Kanepi needed nine tortuous set points before locking down the first 6-4, in shades of her quarter-final win over world No.2 Aryna Sabalenka when she blew four match points to send the contest to a tie-break.
Momentum swung Swiatek's way as she raced to a 4-1 lead in the second set but the gritty Kanepi roared back to level before the young Pole clinched it in a tiebreak.
In a repeat of her three-set quarter-final victory over Sorana Cirstea, Swiatek was never headed in the decider to book her spot in the final four.
Collins returned to the semi-finals after a ruthless straight-sets victory over French veteran Alize Cornet.
The pair went toe to toe in the opening set before the American lifted a gear in the second to sweep through the match 7-5 6-1.
Collins, the 30th seed, made the final four at Melbourne Park in 2019 which is her best grand slam result.
She is the second American into this year's last four, joining Madison Keys.
Collins underwent surgery last year to treat endometriosis, with the condition leaving her in harrowing pain during tournaments last year.
"It feels incredible, especially after some of the health challenges I've had," Collins said in her post match interview.
"To be able to get back to this level and be able to compete like the way I have been and being able to be as physical as I haven't been so rewarding."
It may have been Cornet's last Australian Open singles appearance with the 32-year-old contemplating retirement.