A couple of routine holds of serve by the two Alexanders to start on Centre Court.

Jamie Murray
Seven-time Grand Slam doubles champion on BBC One

The interesting thing about Alexander Zverev is that he has been to each of the Grand Slam finals except for Wimbledon, where he has only ever reached the fourth round.

We have done a deep dive into the reasons behind that and one of the main things is his second serve returns, which has been a limiting factor for him. His inability to return closer to the baseline, in comparison to Jannik Sinner and Carlos Alcaraz, allows his opponents to step into the baseline and put weight behind returns.

Harry Poole
BBC Sport at Wimbledon

What a win that is for Jacob Fearnley!

From two sets down, he becomes the third British singles player through to the second round today.

There were big cheers for Fearnley as he rose up from his chair ready to try to serve out the match - but that’s nothing compared to the noise which greeted confirmation of his hard-fought win after three and a half hours on court 15.

The Briton waves to the crowd before heading over to embrace members of his team, and he is surrounded by fans as he tries to make his way out of the arena.

He disappoints one man who jokingly calls for an exit speech from the 24-year-old, but everyone else will feel they got more than their money’s worth from Fearnley today.

Toby Samuel could not take his momentum in to the second set and finds himself even with 15th seed and French Open semi-finalist Jakub Mensik.

The Czech won 100 percent - yes 100 percent - of his first-serve points in set two and a whopping 80 percent of his second-serve points. That is no joke from the world number 18.

The third set is under way as Mensik holds from 15-40 down. The momentum is very much with the 20 year-old.

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Alexander Zverev has reached finals at three of the four Grand Slams - but not at Wimbledon.

He's the second seed at SW19 this year.

Big-serving American duo Taylor Fritz and Ben Shelton are in his half of the draw, while Italian Flavio Cobolli - the man he beat in the French Open final - is a possible semi-final opponent if Zverev makes it that far.

Alexander Blockx will serve first in the sunshine on Centre Court.

Lois Boisson has broken second seed Elena Rybakina early in the second set!

From 0-40, she was pegged back to 30-40 but kept her cool with a looping lob, which Rybakina, tracking back for the overhead, could only tap back into the court.

Boisson went for the pass with Rybakina at the net and although the former champion got a racquet on it, she sent her volley wide.

Alexander Blockx hasn't played competitively since being forced to withdraw from the French Open because of an ankle injury sustained in a practice session before his scheduled second-round match in Paris.

He has never won a Tour-level match before on grass.

Image source, Getty Images

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It's just 23 days since Alexander Zverev ended his long wait for a first Grand Slam singles title by winning the French Open.

The German's record at Wimbledon isn't the best - he's never been beyond the fourth round and he was beaten in round one by Arthur Rinderknech 12 months ago.

In terms of rankings, the second seed has been handed one of the toughest first-round draws he could have got.

Highly-rated Belgian Alexander Blockx is 36th in the world and making his Wimbledon debut today.

Blockx got to the semi-finals on the clay in Madrid earlier this year, with Zverev denying him a place in the final.

The two players will be walking out onto Centre Court shortly.

Elena Rybakina has taken the first set on court one. The former champion broke Lois Boisson's serve in the opening game and that proved the difference, with Rybakina sealing the set 6-4.

Rybakina had to save two break points in her opening service game and wasted a set point in the ninth game but it's so far, so good for the world number two.

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Defending champion Iga Swiatek, speaking on court after her three-set victory over Taylor Townsend, which included a 21-minute game in the third set: "Sometimes just serving the ball in might be a tough ask so this game for sure was about that and about believing that I can do it because it was long and many break points.

"At the end I'm happy I kept my composure, I was listening to the box and they were supporting me a lot. I know I need to be solid and not look for winners or serves that would give me a point and play more safe to have a chance to play a rally.

"I'm happy in the end that this game went well because I think it was crucial and into the next one."

On whether the challenge today will help Swiatek defend her title: "I think so but on the other hand it also depends on how you react after. I'm happy I could get through a match like that because I got quite tense in the second set and I was able to come back to my game.

"These are the moments where you feel that you did your job because it's not hard when everything goes your way and you're so confident that everything goes in.

"When there are ups and downs this is the time to check how much you can put to change things around and for sure, we'll see [about defending her title] but with my game I feel pretty well and it's just a matter of consistency."

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Is Jacob Fearnley on the home straight?

It is a double break for the Brit in the final set against Alex Michelsen.

The American looked like he wanted to smash his racquet as he sat down, but he resisted. You can hardly blame him for being annoyed with himself, given he was two sets up and flying earlier in the afternoon.

After 10 British defeats on Monday, there has been some home success on day two at Wimbledon:

• Katie Swan became the first British player to reach the second round with a 6-4 6-4 success over Romanian world number 173 Irina-Camelia Begu.
• Arthur Fery overcame a nosebleed to beat Damir Dzumhur 3-6 6-2 6-2 6-1.

But there were more defeats than wins:

• British number two Katie Boulter fell to a disappointing 6-4 6-2 defeat by 18-year-old Italian Tyra Grant, ranked 172 in the world.
• Wildcard Harry Wendelken claimed a set on his Wimbledon debut, but bowed out 4-6 6-3 6-3 6-3 to Valentin Royer.
• Jack Pinnington Jones, who trailed Brandon Nakashima by two sets and 4-3 in the third when play was suspended on Monday, was unable to pull off a miracle comeback and succumbed to a 6-3 7-6 (7-5) 7-5 defeat.

Currently in action are Jacob Fearnley, Toby Samuel and Billy Harris, while Jan Choinski plays later.

Naomi Cavaday
Former British tennis player on BBC Radio 5 Live

It is astonishing to see how emotional Iga Swiatek is after this first-round match. Perhaps it is relief because it is such a difficult task coming out here as defending champion.

That even extends to the walk out to Centre Court because, as Novak Djokovic said, there is nothing else you can liken it to in our sport.

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Iga Swiatek is visibly emotional after that victory, where inconsistencies threatened to derail her title defence.

She takes a few minutes to gather herself before conducting the post match interview on court, which we will have quotes from shortly.

Marion Bartoli
Former Wimbledon champion on BBC Radio 5 Live

You can see the relief on Iga Swiatek's face! She has her face in her towel and she is shedding a few tears. It was a very intense match.

After losing that second set, she actually went off court. The moment it turned was in the very first game of the third set, which saw Swiatek have to save four break points. It was absolutely pivotal and vital because she was really losing the momentum of this match.