The French Open has always had an ability to throw up unlikely finalists and in Sara Errani of Italy, it has come up trumps again.

But in Maria Sharapova, it has offered up not only an intriguing final, but the carrot of history should the Russian finish the job.

While No.21 seed Errani continued her dream run with a 7-5, 1-6, 6-3 upset victory over US Open champion Sam Stosur to reach her first grand slam final, Sharapova saw off Czech Petra Kvitova 6-3, 6-3 to reach her third final in the past four grand slams.

Her third straight win over Kvitova was another small piece of revenge for her defeat by the Czech in last year's Wimbledon final and ensures she will return to the top of the world rankings on Monday for the first time in four years.

Of just as much importance to Sharapova, is that she is into the final here for the first time and victory over Errani tomorrow would mean she joins an elite group to have won all four grand slam titles in their career.

"I was in a position a few years ago where I didn't quite know if I would ever be here again on this stage playing professionally," Sharapova said. "And not just that but at a level to get to No.1 in the world and a first Roland Garros final. So it is a very special day, no doubt.

"All I know is that I've worked hard to get to this place. I'm happy and I'm proud of where I came from and how I had to get here to this position.

"Obviously I really hope that I can stay in this position. It's a spot that you always go for, but it's also a spot that many others want and work hard for, as well, but when you get there it's always even tougher to keep it, so it's certainly a challenge."

At 25, four years after shoulder surgery that threatened to end her career, the Russian coped better than Kvitova with tricky, windy conditions.

The left-handed Kvitova had chances to break in each of Sharapova's first two service games but the Russian held and was always the more solid. "It was tough to play a great match because of the conditions," she said. "I think most importantly it was about playing a solid match. Patience was very important because in conditions like this, no matter how good you're playing or bad, so many things equal out. If you get frustrated by a few mistakes, it can let you down."

Kvitova was generous in her praise for the new world No.1. "I didn't play bad but she was better on the court, she deserved it," she said.

"From the beginning of the tournament I felt well and I played good tennis. Of course it's a bit disappointing now but it is my best result here on the clay in Paris. I will be happy in the next few days."

Stosur went into her semi-final as the huge favourite over Errani, having reached the final here two years ago and played superbly en route to the last four. But despite a solid start, the Australian was tight and nervous and Errani, who has won three titles on clay this year, took advantage.

The Italian played smart, controlled tennis, taking the time away from Stosur by attacking the ball early and even when she was outplayed in the second set, she refused to panic.

"I never thought I could reach the final," said Errani, who is one win away from emulating the victory of Francesca Schiavone, the winner here in 2010. "It's incredible for me. I didn't expect it but it is not finished and I have one match more. I have to think about that. That's it."

Stosur admitted she had been nervous but vowed to return. "I'm capable of doing more, and I didn't for whatever reason," she said. "I'm going to come back next year and the year after and the year after," she said. "Hopefully one day I can win this tournament. I've come close but hopefully one day it will happen."

Today, meanwhile, will be all about the men and the two semi-finals as world No.1 Novak Djokovic takes on Roger Federer while six-times champion Rafa Nadal meets fellow Spaniard and conqueror of Scotland's Andy Murray, David Ferrer.

For Djokovic, it will be a chance to reach his first French Open final, gain revenge on the Swiss for his defeat at the same stage last year and move to within one win of completing his fourth straight grand slam title.

For Ferrer, it is the challenge of beating Nadal on clay for the first time and reaching his first grand slam final. Nadal and Federer have been there and done it many times before.

Something, you feel, has got to give.