World number one Serena Williams survived a huge scare to reach her first French Open semifinal since 2003 on Tuesday, defeating unseeded Russian Svetlana Kuznetsova, 6-1, 3-6, 6-3.
Williams, bidding to win just her second title in Paris, 11 years after her first, looked down and almost out at one stage against the 2009 champion.
She coasted through the first set, but dropped serve for the first time in the tournament, after being broken three times in the second set, trailed 0-2 in the third and fought off two break points that would have seen her slip to 0-3.
However, she battled back, winning six of the next seven games to secure victory in a shade under two hours.
Victory extended Williams’ winning streak to 29 matches as she moved into a semifinal clash against Italian fifth seed Sara Errani, the runner-up to Maria Sharapova last year.
“It was very difficult and I am very tired,” said Williams, who is the first American woman since Jennifer Capriati in 2004 to reach the last four.
“Svetlana played very well. She has won this tournament before so I am happy to get through such a tough match.
“Against Sara, it will be another tough match, she's a great fighter.”
Williams, who had dropped just 10 games in reaching the last-eight, eased through the first set with breaks in the second and sixth games, sealing the opener with an ace, despite the challenges posed by a tricky, swirling wind inside Court Suzanne Lenglen.
The 27-year-old Kuznetsova took a medical timeout off the court and the treatment worked wonders as she broke for a 2-0 lead in the second set.
The wily Kuznetsova, who had defeated the American at the same stage in 2009 on her way to the title, fended off two break points to go to 3-0 and broke again for 4-0 before Williams clawed one back for 1-4.
But the American then dropped serve for a third time to slip 5-1 down as the Russian forced the errors with a clever mix of power, angles and drop shots.
It was a realisation that, unlike too many others on the tour, she was not going to out-bludgeon the world number one and that the key was to keep her moving.
Williams, however, dug deep, got back to 3-5 and then had break points in the 10th game only for a scrambling, netted backhand to give Kuznetsova the set to level the tie.
It was the first set the top seed had dropped in the tournament.
Kuznetsova kept the 31-year-old American on the back foot and was 2-0 up in the decider and had two points for a 3-0 lead.
The Dubai-based Russian couldn’t make that last push and was made to pay as Williams broke back for 2-2. The world number one was quickly 5-2 ahead and she claimed the tie with a rasping cross-court forehand.
Errani reached the semifinals for the second successive year with a 6-4, 7-6(6) win over Polish fourth seed Agnieszka Radwanska.
It will be the third semifinal appearance at a Grand Slam for the slender Italian, who stands at just 1.64m, after she also went to the last four at the 2012 US Open.
Radwanska, the 2012 Wimbledon runner-up, had won the pair’s last three tour-level meetings.
But she was playing in her first Roland Garros quarterfinal, a match which featured 11 breaks of serve.
“There was a lot of pressure because I have a lot of points to defend. That’s a new experience for me,” said Errani, who came into the French Open with a 0-28 record against top-five players.
The remaining quarterfinals take place on Wednesday when Sharapova tackles Serbia's Jelena Jankovic and Victoria Azarenka, the Australian Open champion, faces Maria Kirilenko.
Indian challengers continued to exit from the French Open as Sania Mirza and her American partner Bethanie Mattek-Sands were forced to retire from their pre-quarterfinals following a groin problem to the latter, on Tuesday.
Sania and Bethanie, seeded seventh, had claimed the first set but the American encountered a groin issue in the second set and eventually they pulled out with score reading 7-6(0), 3-5 against 11th seeds Anastasia Pavlyuchenkova and Lucie Safarova.
Earlier on Monday, Sharapova was all business in seeing off American 17th seed Sloane Stephens 6-4, 6-3 to set up a meeting with Serbian 18th seed Jelena Jankovic, who thrashed US hope Jamie Hampton 6-0, 6-2.
Sharapova, who in beating Sara Errani in last year's final became the sixth player in the Open era to complete a full collection of Grand Slams, was rarely troubled by Stephens, Australian Open semifinalist last January, the Floridian 20-year, gifting her a final break by hitting long on match point.