Serena Williams made a shock exit from the French Open. Photo: Christophe Ena/AP Photo

PARIS Serena Williams' bid to win a record-equalling 24th Grand Slam title was thwarted again when she suffered her earliest exit at the majors in almost five years, leading to more questions over her long-term future at the highest level.

Her 6-2, 7-5 French Open third round defeat by US compatriot Sofia Kenin meant that she failed again to move level with Margaret Court's majors record set between 1960 and 1973.

The bare figures do not making encouraging reading.

Williams will be 38 in September while her 23rd and most recent Slam triumph was at the Australian Open in 2017 while pregnant.

After giving birth to daughter Alexis Olympia in September 2017, she returned to Grand Slam tennis at Roland Garros in 2018, making the last 16 where she had been set to resume her bitter rivalry with Maria Sharapova.

An arm injury torpedoed that meeting and stalled her assault on a fourth title in Paris after 2002, 2013 and 2015.

Defeat in the 2018 Wimbledon final to Angelique Kerber, and at the US Open championship match, where her now-infamous meltdown overshadowed Naomi Osaka's title triumph, followed her Paris heartbreak.

Her Australian Open campaign in January ended in a quarter-final loss to Karolina Pliskova despite having led 5-1 in the final set and holding four match points.

Since Melbourne, Williams had been unable to finish the three tournaments she entered -- she retired to Garbine Muguruza in the third round of Indian Wells, withdrew after winning a round in Miami, and pulled out after winning one match on the Rome clay due to a right knee injury. 

Saturday's loss was her earliest exit at the Slams since a third round defeat to Alize Cornet at Wimbledon in 2014.

Despite that grim record, the American, who was seeded 10 in Paris, is determined to return to the peak of her powers.

- 'I can start putting the time in' -

"If I was told I would only make the third round here, I would have thought they were lying, because I wouldn't expect to have gotten only to the third round," said Williams after her loss on Saturday.

Williams said she will try again to equal Court's record at Wimbledon in July where she will be chasing an eighth title at the All England Club.

"I'm just pretty far away, but the optimistic part is I haven't been able to be on the court as much as I would have," she said, adding that she may even take a wildcard into a pre-Wimbledon event.

"At least I can start trying to put the time in now. It's just been a really gruelling season."

Kenin, who wasn't even born when Williams made her Paris debut in 1998, revealed that the two had tentatively planned to practice together at the start of the season.

"I texted Patrick (Serena's coach Patrick Mouratoglou) during pre-season. Serena wanted to hit. 

"I was so happy when he answered me. I was, like, 'Oh, my God, Patrick texted me'. And he said, like, we'll keep in touch.

"It wasn't possible, but I'll take that. I'll take the win over the hitting. Saying it nicely."

Kenin goes on to face Australia's Ashleigh Barty for a place in the quarter-finals.

At 20, Kenin is a veteran compared to 17-year-old Amanda Anisimova, 18-year-old Iga Swiatek and Marketa Vondrousova who is 19.

Their run to the fourth round marks the first time since 2009 that three teenagers have made the last 16 at a Slam.

Anisimova, who made the fourth round at the Australian Open in January, is the youngest woman to reach the last 16 in Paris since Martina Hingis in 1998.

"I feel really great that I have been doing so well at my young age," said Anisimova.

Swiatek only celebrated her 18th birthday on Friday and despite sharing a landmark moment for teenagers in Paris with Anisimova, the two have some differences.

The Pole counts AC/DC and Pink Floyd on her playlist while the American prefers rapper Drake.

"Some people you probably don't know, like A Boogie wit da Hoodie, and just, like, the new rap," she explained to puzzled reporters.

AFP