Paris, France, 2 June 2016 | AAP

Sam Stosur has kept alive her dream of adding a French Open title to her collection by seeing off Bulgaria’s Tsvetana Pironkova in a gruelling quarterfinal.

With the clouds closing in on Roland Garros, Stosur survived a tense tiebreak to prevail 6-4 7-6(6) in a little under two hours and advanced to the final four for the fourth time – adding to a run to the final in 2010 and semifinals in 2009 and 2012.

“I think typically whoever wins a Grand Slam, they don’t always play their best tennis every single day, but they find a way to win,” said Stosur, who will rise to at least No.14 in the world following the win.

“That’s what I was able to do today.”

Stosur will next play fourth seed Garbine Muguruza on Friday for a spot in Saturday’s final, with the Spaniard downing American outsider Shelby Rogers in straight sets.

“She hits the ball hard and flat. It’s going to be hard,” Stosur said.

The women on the other side of the draw – including world No.1 and favourite Serena Williams – will play their quarterfinals on Thursday as organisers attempt to reorganise the schedule following many rain delays.

Stosur started slugglishly in the cool conditions on Wednesday and was twice broken in her opening three service games to go down 4-2 in an error-strewn opening to the match.

She was on the cusp of being broken again, giving up triple break point which would’ve seen her go 5-2 down and on the edge of conceding the first set.

However Stosur would save all three – letting out a motivating “c’mon” in the process – in a game which would prove the match’s turning point.

Stosur would win the next five games as her rhythm returned, closing out the first set in 41 minutes.

“Obviously that was a big moment. 5-2 is a hell of a lot different to 4-3,” Stosur said.

“And then it’s probably even more so when they have just had three break points and really almost feel like they are in total control of the match.

“That was a really crucial part of the match.”

With her head clear, Stosur returned to the sort of form which helped take down the past two beaten French Open finalists, Lucie Safarova and Simona Halep.

However with her French Open survival on the line, Pironkova responded to break Stosur early in the second and open up a 3-1 lead.

Stosur then won three games on the bounce to regain control of the set.

As clouds darkened and rain threatened to return, Stosur was able to ice the quarterfinal by fighting back from 1-5 in the tiebreak.

After saving two set points, Stosur forced an error from the Pironkova forehand to take the win and the semifinal berth.