Czech Barbora Krejcikova is into her first Grand Slam semi-final after seeing off American teenager Coco Gauff in a nervy French Open encounter.

The 25-year-old eventually wrapped up an intriguing quarter-final battle in one hour and 50 minutes in Paris.

"I never imagined I would be standing here one day," she said.

"Already for me this is something I have never dreamed of. I was really playing a great match and Coco is incredible - she is 17, it's amazing."

The world number 33 will face Polish defending champion Iga Swiatek or Greece's Maria Sakkari for a place in the final at Roland Garros.

Eighth seed Swiatek is the highest ranked woman left in the draw.

Frustrated Gauff slips to defeat

Gauff made the perfect start to her first Grand Slam quarter-final, eventually seizing her fourth break point in Krejcikova's opening service game as she opened a 3-0 lead on Court Philippe Chatrier.

But Krejcikova, also appearing in her first major singles quarter-final, rallied impressively to claw back the deficit - surviving another break point before holding to level at 3-3.

Gauff, junior champion in 2018, held firm under pressure on serve before breaking the Czech for a second time but her failure to take her first set point allowed Krejcikova a way back.

The American responded admirably, unleashing a powerful forehand winner on her way to a comfortable hold at 6-5, but Krejcikova rescued two more set points - one with a superb line shot - to set up a nervous tie-break.

Gauff battled back from 2-0 behind to set up her fourth set point at 6-4 before a steely Krejcikova once again dug in to win four successive points and take the opening set.

Gauff failed to convert a break point in the first game of the second set and her hopes unravelled from there as Krejcikova held serve and immediately earned a break of her own.

The 25-year-old, who knocked out fifth seed Elina Svitolina in the third round, then moved 4-0 ahead as a frustrated Gauff double-faulted before smashing her racquet on the clay.

Gauff showed resilience to hold serve to get on the board at 5-1, staved off three set points to claw one break back, and then held again for 5-3, but Krejcikova eventually closed out at the sixth time of asking to reach the last four at Roland Garros for the first time.

"I am very happy, thank you very much for coming today," she told the crowd. "It was amazing, you gave us so much energy."

Anastasia Pavlyuchenkova will face Tamara Zidansek in the other women's last-four meeting after both players reached maiden Grand Slam semi-finals on Tuesday.

Russia's Pavlyuchenkova came from a set down to beat her doubles partner Elena Rybakina 6-7 (2-7) 6-2 9-7, while Slovenian world number 85 Zidansek claimed a hard-fought 7-5 4-6 8-6 win over Spain's Paula Badosa.