Defending champion Elena Rybakina booked her place in the Wimbledon third round but only after surviving a torrid second set against experienced Frenchwoman Alize Cornet, who needed a medical timeout after slipping late in Thursday's contest.

On paper the 6-2 7-6(2) win looked comfortable enough but it was far from straightforward as Rybakina's power game which initially looked devastating began to malfunction badly.

From seeming as though she would be back in the locker room in little more than an hour, she was eventually relieved to get off after a second set that lasted 82 minutes.

She will now face wildcard Katie Boulter, Britain's last remaining player in the women's draw.

"I started the match good. I had good energy but in the second set it became tougher," Rybakina, who took Wimbledon by storm to win the title last year, said on court.

"It was a tricky long game and also Alize's fall. It was a tough match but I'm happy to win in two sets."

The Moscow-born Kazakh began like a whirlwind against her 33-year-old opponent, slamming winners all over Centre Court in a 26-minute opening set.

But her game went from red hot to decidedly lukewarm as the wily Cornet, playing in her 66th successive Grand Slam tournament, a women's professional era record, used all of her experience to gain a foothold.

Cornet reached her first Grand Slam quarter-final at this year's Australian Open and stunned Serena Williams at Wimbledon in 2014 as well as knocking out top seed Iga Swiatek at last year's championships.

Extending the rallies, she gradually began to extract wild errors off the Rybakina racket.

The third seed was rocking at 5-5 when she slipped 0-40 down on serve, but clawed her way back.

A marathon 11th game, made even longer by Cornet's medical timeout after she slipped awkwardly behind the baseline, contained five break points for Cornet and 10 game points for Rybakina before the Kazakh held with a backhand winner.

With the Centre Court gradually filling up in anticipation of local favourite Andy Murray's blockbuster against fifth seed Stefanos Tsitsipas, Cornet took the match into a tiebreak.

But an erratic Rybakina eventually managed to settle down and get the job done.