PARIS — With the unbridled joy of a kid reaching heights she never has, and the go-for-it strokes of someone too bold to know better, an unseeded 19-year-old from Latvia, Jelena Ostapenko, beat former No. 1 Caroline Wozniacki 4-6, 6-2, 6-2 at the French Open on a rainy Tuesday to reach her first Grand Slam semifinal.
Ostapenko sent shots toward the lines and put them right where she wanted often enough to deliver 38 winners — 32 more than the defensive-minded Wozniacki, a two-time runner-up at majors.
“I knew,” the 47th-ranked Ostapenko said, “I had to be aggressive all match.”
Ostapenko’s next opponent is 30th-seeded Timea Bacsinszky of Switzerland, who eliminated 13th-seeded Kristina Mladenovic of France 6-4, 6-4.
Both women’s quarterfinals were interrupted twice because of showers; the first delay lasted more than 3 hours, the second about a half-hour. The men’s quarterfinals involving Rafael Nadal and Novak Djokovic that had been scheduled for Tuesday were postponed until Wednesday.
The last two women’s quarterfinals are also Wednesday: No. 2 Karolina Pliskova of the Czech Republic vs. No. 28 Caroline Garcia of France, and No. 3 Simona Halep of Romania vs. No. 5 Elina Svitolina of Ukraine. This is the first Grand Slam tournament since the 1979 Australian Open that none of the eight women’s quarterfinalists had won a major title.
When Tuesday’s play began, the wind averaged 18 mph (30 kph), with gusts up to 50 mph (85 kph), making balls swerve oddly. Serve tosses were an adventure. Players repeatedly wiped their eyes to get rid of dust kicked up from the clay court. By the final resumption, the temperature was below 55 degrees (12 Celsius).
“We had all the seasons rolled into one today. We had a hurricane, a sandstorm, and we almost had snow, too,” Bacsinszky told the crowd at Court Philippe Chatrier. “It was really tough to keep my concentration all day long. I feel exhausted — and I’m sure you do, too.”
Ostapenko had the most trouble in those conditions, quickly trailing 5-0.
She calibrated her strokes better as time went on and the air swirled less, taking four games in a row to make the first set interesting before ceding it. Still, it was clear that she was up to the task against the 11th-seeded Wozniacki, who is 26 and has been to two U.S. Open finals and yet somehow seemed the less sure of herself.
Then again, this was a matchup that clearly suits Ostapenko: She is now 4-0 against Wozniacki.
“Her shots are hard to read,” Wozniacki said, “so you don’t really feel comfortable at any point in the match.”
Ostapenko was down 2-1 in the third set before taking the last five games, serving it out at love. When the match ended, she smiled and shouted and pumped her fist.
Ostapenko’s rise has been swift.
She is the youngest French Open semifinalist in a decade. And she is the first Latvian woman to reach a Grand Slam semifinal in the professional era, which began in 1968.
She has yet to win a tour-level title of any sort.
A year ago, Ostapenko lost in the first round of the French Open.
The year before that, she lost in the first round of French Open qualifying.
Before last week, she had never been past the third round of any Grand Slam tournament.
“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 of her fearless opponent, “and she does anyway.”
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.
For Bacsinszky, it will be only slightly more familiar territory. She has played in one previous major semifinal, also in Paris, losing to eventual champion Serena Williams two years ago.
Four years ago, after her time on tour was limited by foot and abdominal injuries, she took a hiatus from tennis to work at restaurants with an eye toward pursuing a degree in hotel management.
In 2014, she was ranked outside the top 100 and went through qualifying at the French Open.
But Paris has become a site that brings out her best tennis.
“It’s the tournament closest to my heart,” Bacsinszky said. “I love to play here.”