Aliaksandra Sasnovich is a 27-year-old from Belarus and is ranked 100th in the world, 92 places behind Serena Williams, however, Sasnovich has been as high as 30th.

Sasnovich has only got past the second round of Wimbledon once, in 2018 when she made it into the last 16, but lost to Jelena Ostapenko.

That run three years ago was Sasnovich's best run in a Grand Slam and this is the first meeting between the pair.

Serena Williams says she is not taking opponent Aliaksandra Sasnovich lightly. Williams said: “I think the women’s draw is so deep, regardless who you play.

“You really have to show up now. There’s no longer matches that are going to be a sure walk-through. You just have to really have your head in, have your game on.”

Williams has not won a grand slam title since the Australian Open in 2017 but remains the biggest scalp in women’s tennis.

She said: “It’s definitely made me better. I’ve had a big X on my back since ’99, since I won the US Open. When players play me that hard every single tournament, every single match, every single grand slam, it just doesn’t matter where, you just get better.

“It’s been difficult mentally when someone might beat you and they lose directly in the next round almost every time. At the end of the day, that’s why I’m Serena.”

We're under way on the Centre Court in the match between Aliaksandra Sasnovich and Serena Williams and it's 1-1 in the match between the world number 100 and the world number eight.

Daniil Medvedev keeps presenting himself with opportunities to break but Jan-Lennard Struff is fending them off! Another classic Medvedev lob but some meaty serving from the German saves him again from two break points down.

Katie Falkingham
BBC Sport at Wimbledon

Coco Gauff has gone a break ahead in the second set against Fran Jones. Two more games and this tie is hers.

The winner of this match will face Elena Vesnina or Martina Trevisan in the second round. They are yet to get their opener under way.

John McEnroe
Three-time Wimbledon singles champion on BBC TV

You've got to give Struff a lot of credit, he's hit some extremely difficult shots in this game alone. He is battling hard.

But then Medvedev is saying to the crowd, 'Cheer for me now, appreciate what I'm bringing to the table.' It would really do him some good now to finish this feisty German, Struff, off.

Image source, Getty Images

Daniil Medvedev brings up a break point in the fourth set with a delightful lob but Jan-Lennard Struff hangs on in the next rally and the Russian goes long.

Superb fight back to hold serve by the German - this is quite the tussle!

French Open champion Barbora Krejcikova has taken the first set on her debut main draw appearance.

The Czech leads Clara Tauson 6-3 2-0.

Kiki Bertens is trying to overturn a first-set deficit against Marta Kostyuk, while Anna Blinkova leads Timea Babos 4-1.

Either Blinkova or Babos will face world number one Ash Barty in the second round.

Image source, Getty Images

John McEnroe
Three-time Wimbledon singles champion on BBC TV

Medvedev is getting edgy, he's starting to pile off a bit and Struff senses it. There's a bounce and a belief to Struff now that wasn't there not long ago.

Will this be the year that Serena Williams equals Margaret Court’s record of 24 Grand Slam singles titles?

The American last won a major at the Australian Open in 2017 and later revealed she had been pregnant at the time. And Williams has been unable to add to her tally since her comeback from giving birth to daughter Olympia.

Wimbledon appears to be her best chance of doing it having made it to the last two finals, but on both occasions she was outplayed – by Angelique Kerber in 2018 and then Simona Halep 12 months later.

Williams has won seven singles titles on Centre Court so it would be the fitting place to do it and an early 40th birthday present before her landmark in September.

Aditya: The post match interview... Federer showing he is human after all. THAT is why he will always be the GOAT, whether he has the highest number of slams or not.

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More from Roger Federer: "I tried to cut down the length of points, he found a nice groove from the baseline with that shovel backhand and did the same to me, once I got the break I was able to loosen up a little bit.

"It was a very up and down match and overall we were both wrestling to see who could enjoy the baseline, I felt I had to adjust my game more than he did his and that's credit to him.

"It is such a privilege to play here."

Asked about absence making the heart grow fonder after being away from Wimbledon... "I don't understand the question! A good reminder my English is not very good.

"It would have been the worst to have this tournament with no fans, it would have been an absolute killer."

It's game on over on Court One as Jan-Lennard Struff takes the third set, sealing it 6-4, against second seed Daniil Medvedev.

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Here is Roger Federer: "It is awful and shows one shot can change the outcome of a match, season, career and I wish him all the best and hope we see him back quickly - he was the better player, he could have won, I got a bit lucky.

"That's how it goes sometimes, you don't get many walkovers and try not to have it happen to yourself, it is a reminder how quickly it goes but I am obviously happy I can get another match here - I enjoyed myself today and it was great fun until the end."

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Jan-Lennard Struff is serving for the third set. It looked all over with Medvedev breezing through the second set, but the German could pull one back very soon.

John McEnroe
Three-time Wimbledon singles champion on BBC TV

Medvedev has got to be pretty upset with himself that he's let this become a match - because it was looking like it could be a rout. Now it looks as though it's going to go four sets at least.

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