Paris - Swiss 30th seed Timea Bacsinszky reached the French Open semi-finals for the second time on Tuesday with a rain-hit 6-4, 6-4 win over home hope Kristina Mladenovic.
The 27-year-old, who also made the last four in 2015, will face unseeded Latvian Jelena Ostapenko who stunned Danish 11th seed Caroline Wozniacki 4-6, 6-2, 6-2 for a place in Saturday's final.
"I feel extremely privileged to be in a second semi-final at Roland Garros," said Bacsinszky, whose run to the last four two years ago was ended by Serena Williams in three sets.
Tuesday's match was one hour 49 minutes in duration but took the best part of six hours to complete after two rain delays -- one lasting three hours.
"It was extremely difficult today. There was fine weather, then rain, wind and the clay was blowing in our eyes.
"I had to stay concentrated. I am sorry for the crowd but happy for me."
She will be joined in the semi-finals by teenager Jelena Ostapenko who became the first Latvian woman to reach a Grand Slam semi-final after defeating Caroline Wozniacki 4-6, 6-2, 6-2.
The unseeded 19-year-old will face Bacsinszky for a place in Saturday's final.