Krejcikova ends Gauff's Roland Garros run

Barbora Krejcikova has made it into the semi-finals of the French Open, the Czech doubles specialist ending the run of American teenager Coco Gauff.

Barbora Krejcikova has become the latest unexpected French Open semi-finalist, the doubles specialist finally putting an end to teenage star Coco Gauff's never-say-die challenge at Roland Garros.

Krejcikova, who's won five grand-slam doubles crowns but had never previously been beyond the fourth round in singles, worked wonders to save five set points in a mistake-riddled opening set before advancing 7-6 (8-6) 6-3 on Wednesday.

"I certainly never imagined I'd be standing here one day. This is something I never dreamed of," Krejcikova, the world No.33 told the crowd.

The 17-year-old American Gauff was cutting a dispirited and angry figure, warned for smashing her racquet into the Court Philippe Chatrier clay after her game completely unravelled at 4-0 down in the second set at the hands of the doughty Czech.

But the teenager, who'd surrendered 15 straight points as she went 5-0 down, rallied magnificently from 5-1, 40-love behind with Krejcikova serving for the match.

Gauff, remarkably, saved five match points in all as she fought back to 5-3 but Krejcikova, who was ranked outside the top 100 a year ago, finally prevailed after an hour and 50 minutes, roaring in delight as Gauff finally clouted a forehand wide on the sixth match point.

"When she saved those points I told myself, 'you got to be aggressive, just go for your shots. If you're going to stay aggressive, it's not going to slip.' That's what I was telling to myself," said Krejcikova.

The 25-year-old, who admitted she was left crying with nerves before her previous round victory over Sloane Stephens as she questioned whether she could play in such esteemed company, found again that she now really does belong at the highest level.

She did have to fight with herself again, veering between outright fragility with her wayward ball tosses and serving but also delivering winning forehands that twice saved her at set point down in the tiebreak.

Even at 3-0 and then 5-3 down in the opening set as Gauff's extra power paid early dividends, Krejcikova, who'd won her maiden WTA tour event in Strasbourg the week before Roland Garros, kept smiling, evidently relishing the fray.

"I just tried to stay, really really calm and that's my big weapon. I was never actually expecting to be here so I'm just happy it's happening and I'm enjoying it," she explained.

Krejcikova will next meet Greece's Maria Sakkari, who caused a sensation later on Chatrier by knocking out champion Iga Swiatek in straight sets.