Romania's Simona Halep clenches her fist after defeating Karolina Pliskova of the Czech Republic during their semifinal match at Roland Garros on Thursday.David Vincent / Ap

PARIS - If Jelena Ostapenko beats Simona Halep to win the French Open on Saturday, she will become the first tennis player - male or female - in 20 years to earn a first tour-level title at a Grand Slam.

The last to do it? Gustavo Kuerten, who won the men's trophy at Roland Garros on June 8, 1997.

Unseeded, ranked only 47th and never before past the third round at any major tournament, Ostapenko is about as surprising a finalist as there can be on this stage.

That's not to say there haven't been others, of course.

And the French Open, with its slow clay that can act as an equalizer - it dulls the impact of the biggest serves and strongest groundstrokes, and calls for different footwork from hard or grass courts - and its ever-changing weather conditions, tends to produce unexpected runs to the last weekend.

Kuerten, for example, was ranked only 66th in 1997. He went on to collect two more French Open titles and was elected to the International Tennis Hall of Fame.

But as Kuerten recalled on Thursday: "I came to Roland Garros for the first time just hoping to win one match.

"That would have been enough. I never had passed the second round in any Grand Slams. I had played three in all my life. So this was a kind of run you normally don't see."

In the two decades since his triumph, men such as Andrei Medvedev (1999), Martin Verkerk (2003) and Mariano Puerta (2005) have been runners-up at the French Open. And Albert Costa (2002) and Gaston Gaudio (2004) actually won the whole thing in Paris.

Ahead of Ostapenko's title match against Halep on Saturday, here's a look at some other out-of-nowhere women's Grand Slam finalists:

Pennetta vs Vinci, 2015 US Open

That neither had been to a major final before was maybe the least remarkable thing about this matchup between two women from southern Italy who were childhood friends, then doubles partners and roommates as teenagers.

It was the first time since WTA computer rankings began in 1975 that both US Open women's finalists were from outside the top 20. Flavia Pennetta, 33, became the oldest woman in the Open era, which dates to 1968, to become a Grand Slam champion for the first time - then announced her retirement to the world, right there on the court.

Roberta Vinci, 32, would have been the oldest. The most unbelievable part of Vinci's participation was that she stunned Serena Williams in the semifinals, ending the American's attempt to pull off a calendar-year grand slam.

Anastasia Myskina, 2004 French Open

Myskina was seeded sixth, but there was little reason to believe she would become the first Russian woman to win a Grand Slam title: Her career record at Roland Garros was 1-4 entering the 2004 tournament. But she beat major champions Venus Williams and Jennifer Capriati and even saved a match point on the way to the final.

It had been more than 40 years since a woman won the French Open after being one point from defeat.

Myskina's opponent, Elena Dementieva, made it the first French Open final since 1981 with two participants making their debuts in a Grand Slam title match.

Marion Bartoli, 2007 and 2013 Wimbledon

There's never been an unseeded woman in a Wimbledon final during the Open era. But Bartoli played in a couple of title matches there that came close.

In 2007, she was seeded 18th when she lost to Venus Williams, who was 23rd, making the lowest pair of women's finalists in tournament history. And in 2013, Bartoli was 15th when she beat Sabine Lisicki, who was 23rd; that marked only the second time in the Open era that two women without a Grand Slam trophy met for the Wimbledon championship.

Bartoli's 2013 title stands out for other reasons. It was her 47th Grand Slam tournament, the most ever played by a woman before earning a championship.

She had gone more than 1 years without winning a title at any level. And she remains the only woman in the Open era to win Wimbledon playing two-fisted forehands and backhands.

Francesca Schiavone, 2010 French Open

A year after losing in the first round at Roland Garros, the 17th-seeded Schiavone became the first woman from Italy to reach a Grand Slam final - and then won the title.

It was her 39th major tournament and she'd never been ranked in the top 10 until two days after hoisting the French Open trophy. Schiavone won the 2016 Rio Open by defeating Shelby Rogers in the final, ending a three-year title drought.

Karolina Pliskova, 2016 US Open

Pliskova had never been past the third round in 17 previous appearances at majors, but she stunned Serena Williams in the semifinals before losing to Angelique Kerber in the final at Flushing Meadows last September. Pliskova would have reached a second Grand Slam final and jumped to No 1 in the rankings next week, but she lost to Halep in the semifinals.

Associated Press