Troubled sleep, then a French Open dream for Bacsinszky

Ostapenko, an unseeded 19-year-old from Latvia, displayed unbridled joy after using the go-for-it strokes of someone too bold to know better to beat former No. 1 Caroline Wozniacki 4-6, 6-2, 6-2 at the French Open on a rainy Tuesday.

"I actually didn't expect that it would be here in Paris (for my birthday), but I am really happy it's here".

Ostapenko has exceeded expectations at Roland Garros, marching into the last four of a major for the first time by beating Caroline Wozniacki in a match which eventually finished after 8pm local time following two breaks due to the weather.

These included a quarter-final match between fourth seeded Rafael Nadal of Spain and his 20 seed compatriot Pablo Carreno Busta.

"I had to stay concentrated".

It is windy on both courts and dust from the clay is getting in players' eyes.

"So it was a big drama, so I could not get into the plane without giving the towels of the French Open, and I woke up and I was sweating".

Mladenovic, bidding to be the first Frenchwoman in the semi-finals since Marion Bartoli in 2011, was broken in her first service game by Bacsinszky before she levelled at 2-2. Ostapenko's victory occupied 1hr 53min, and Bacsinszky's 1hr 49min, which brought both matches in under the minimum-play requirement of two hours. "I just have to go out there and just do my best", she said.

"There has always been a kind of magic here for me", said the Swiss star after Tuesday's rain-interrupted match which took nearly six hours to complete. Bacsinszky didn't back down, fighting it off on an aggressive passage of play before bringing up match point with a perfectly placed victor down the line.

"It looks like she hits it late a lot of the time, and you think she won't be able to do cross-court or down the line in certain moments", Wozniacki said, "and she does anyway".

Bacsinszky didn't let her guard down after the break and held serve twice to win the set 6-4.

Ostapenko took only two of 11 break points in the first set, but was more clinical when the chances continued to come in the second set.

"It was really hard because we had all the seasons rolled into one today", Bacsinszky said of a day that saw rain and hail.

She certainly needed quick footwork to handle the bad wind that wreaked havoc on her quarter-final with Caroline Wozniacki on Tuesday.

In fact, one of them will reach their first Grand Slam final, with neither having gone beyond the semi-final stage and, incredibly, Ostapenko had never been beyond the second round before the start of 2017! "We had a hurricane, a sandstorm, and we nearly had snow, too". However, she lost her serve trailing 4-5 to hand the first set to Wozniacki.

The sixth seed's single-handed backhand ranks as one of the best shots in men's tennis but so far it has been feeble against Djokovic who he has scraped one set against in five matches and who thrashed him 6-1, 6-0 in the Rome semifinals. But her nerves jangled through a fitful night of sleep before the quarterfinal, and she awoke from an anxious dream sweating, convinced she was on her way to another tournament and had forgotten souvenir towels she'd set aside for her siblings.

Now Ostapenko will play for a berth in the final Thursday, which just so happens to be Ostapenko's 20th birthday and Bacsinszky's 28th.

But their outings have been put back a day, joining the other two men's quarter-final clashes.