Here are the numbers from Katie Swan's succesful first set.

She'll be serving to start te second.

Image source, IBM

We're rattling through the games in the second set so far out on court 12, with three games done in only eight minutes, and we're still on serve with neither player having a chance of a break yet after Peniston took the opening set.

Is that the set for Katie Swan?

She's celebating as a Marta Kostyuk shot flies long over the baseline, but the Ukrainian challenges...

...And long it is! That is an excellent recovery job from Swan against a player who is 108 places above her in the world rankings.

David Law
Commentator on BBC Radio 5 Live

There is a total change in Katie Swan's demeanour out there. A lot more confident and she has really settled on to this court.

The pressure now builds on Marta Kostyuk who is actually the younger of the two players, despite her higher ranking.

Henri Laaksonen is 30 years old, but is only playing in his second match at Wimbledon, having gone out in the first round back in 2017.

He was broken in the first game of the first set, but has avoided the same fate at the start of the second with a routine hold, before Peniston, who was born in the Essex seaside city of Southend, made it 1-1.

Excellent grit from Katie Swan.

A big first serve and a one-two punch stave off two break points against Marta Kostyuk, before an ace down the T wraps up a hold.

That means Marta Kostyuk will have to serve to stay in the first set, having already seen a break lead slip.

Harry Poole
BBC Sport at Wimbledon

It’s a case of so far, so very good for Ryan Peniston on his Wimbledon debut.

The British number six wraps up the opening set courtesy of that single break of serve against Henri Laaksonen 6-4, but there have been some lovely shots from the racquets of both players.

A big roar from Peniston before taking his seat, and the crowd let him know they’re right behind him.

Following Matteo's Berrettini sad withdrawal because of Covid-19, the first match on Court One at 13:00 BST will now be Aussie 19th seed Alex de Minaur v Hugo Dellien of Bolivia. They were originally scheduled for court 18.

That will be followed by the final set of Britain's Heather Watson against Tamara Korpatsch before Simona Halep and Stefanos Tsitsipas close out the programme.

Colin Fleming
British tennis player on BBC TV

Ryan Peniston has started with a bang - broke in the first game and that made the difference.

But expect this second set to be much closer.

What a day this could be for Ryan Peniston, the British world number 135. This is only his second ever match at Wimbledon after going out in the first round of the men's doubles last year, with this his first appearance in the singles.

The 26-year-old has just taken the opening set against Switzerland's Henri Laaskanen.

Peniston broke the serve of the Swiss player, who at 96th is 39 places above him in the rankings, in the opening game of the match and that proved critical.

There's a change of opponent for Britain's Sonay Kartal when she makes her Grand Slam main draw debut a little later on.

Kartal had been due to play Danka Kovinic of Montenegro, but the 27-year-old has withdrawn with a lower back injury.

Kartal will now face Lesley Pattinama Kerkhove of the Netherlands.

That match is due to get under way on Court 16 from around 12:30 BST.

Image source, Getty Images

Melanie South
Former British Fed Cup player at Wimbledon

Katie's done so well. She could have been phased by that early slip but she has just been building herself back.

Sonia Oxley
BBC Sport at Wimbledon

Over on Court 18, Britain’s Katie Swan has recovered from an early break of serve by Marta Kostyuk and is starting to find her range.

That early slip on the grass really seemed to shake her for a while and she was still saying at one changeover “it’s slippery”.

But she seems to be growing in confidence and she is feeding off an enthusiastic crowd - there’s barely a spare seat here.

Ryan Peniston is now serving for the first set in his match against Henri Laaksonen.

Katie Swan is going well in her opener against Marta Kostyuk.

The Briton has just reeled off three games in a row to overturn a break deficit and get proceedings back on serve.

Swan, a wildcard at the Championships, claimed a superb win over US Open champion Sloane Stephens at Bad Homburg last week. The two then paired up for the doubles, which might have been a bit awkward...

Image source, Getty Images

In the women's draw, Maria Sakkari, the Greek fifth seed, is ripping through her match, taking the first set 6-1 against Australia's Zoe Hives

Latvia's Jelena Ostapenko, seeded 12th, is also racing ahead in her match against France's Ocean Dodin, leading 5-2 in the first.

Perhaps one of the feistiest matches out on court today, France's Alize Cornet leads Kazakhstan's Yulia Putintseva 4-3 on serve.

Spanish youngster Carlos Alcaraz produced one of the best shots from the opening day of Wimbledon with Emma Radacanu and Kwon Soon-woo also producing great tennis.

Watch the best action from Monday's play here...

In the men's draw, Belgium's David Goffin is quickly up an early break on Moldova's Radu Albot.

Grigor Dimitrov, who reached the semi-finals here way back in 2014, is on serve in his opener against Steve Johnson over on Court Two.

You can take your pick of which court to watch over here.

Image source, Getty Images

Feel free to send us your thoughts on all the action today at Wimbledon. Get involved by messaging us using #bbctennis or Twitter

Marin Cilic, runner-up at Wimbledon in 2017, also withdrew yesterday after testing positive for Covid-19.