India, June 5 -- In this wild, wild French Open where the defending champion crashed in the first week and the world No.1 imploded early in the second, a teenager has held the fort for the top seeds in the women's draw.

That's saying something about Mirra Andreeva, a hugely talented but also, as recent history suggested, highly volatile 19-year-old who had been primed for Grand Slam glory in the near future. On Thursday, she stood one step away from the crown.

The world No.8 Russian outplayed Ukrainian Marta Kostyuk, the 15th seed who hadn't been beaten on clay this season and brushed aside Andreeva in the Madrid Open final a month ago, 6-1, 6-3 to make her first Slam final.

She is the third-youngest Roland Garros singles finalist of t...