Tim Henman
Former British number one on BBC One

I was speaking to Charlie Gomez, who is part of Novak Djokovic's team, and he told me these two have practiced together a few times. In practice, he has always been impressed by Roman Safiullin's ball-striking.

He sometimes plays with that air of freedom, almost like he doesn't really care and he is just going to go for his shots. That can be unsettling for some players.

Roman Safuillin holds to 15.

These past two games will be a real confidence boost for the world number 132.

A magnificent drop volley, on the stretch, to put him 40-15 up in that game shows he's starting to settle into this one.

Image source, PA Media

The trend of players struggling on serve continues as Jessica Pegula breaks back, but then can't hold serve to stay in the first set.

Iva Jovic brings up three set points and makes them count as Pegula is unable to deal with a backhand return across court.

There's been seven breaks of serve so far and that's the first set Pegula has dropped at Wimbledon this year.

John McEnroe
Three-time Wimbledon singles champion on BBC One

I'm surprised to see that type of service game from Novak Djokovic after getting a quick break.

Roman Safiullin has to mix up his serves now and try to keep his opponent off balance, if possible.

Image source, Getty Images

Roman Safuillin breaks back immediately!

An uncharacteristically sloppy service game from Novak Djokovic as a double fault gives Safuillin an opening at 15-30.

The qualifier brings up two break points and although Djokovic clicks into gear to save both, he loses focus to offer up a third.

A backhand goes wide and we're back on serve.

Also, I'm not sure what the issue is - perhaps sweat in his eyes or the sun? - but Djokovic keeps rubbing his eyes with his shirt. So I don't know if that was affecting him?

Tim Henman
Former British number one on BBC One

We are just three minutes in and we are seeing Novak Djokovic just start absolutely impeccably. He is so clean in his movement, his balance and his ball-striking.

He has sent an early message to Roman Safiullin.

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

Novak Djokovic's serve quality has been seriously impressive throughout this tournament. He has served up a lot of variety as well as painting the lines. He has hit 42 aces so far in the tournament.

The accuracy has been a big part of things, for example 79% of his serves have been within 2 feet of the tramlines. It is seriously impressive that he has won 93% of his service games at Wimbledon this year.

If you consider the fact that he is also probably the greatest returner of all-time, it is a deadly combo.

John McEnroe
Three-time Wimbledon singles champion on BBC One

Roman Safiullin has got some pretty good zip on his serves. I saw him hit 126 and 127mph in that service game. It isn't as if he hits a lot of aces, I think he has only hit one, but he seems to set himself up for the next ball pretty well.

But it was a quick break for Novak Djokovic, it looks like reputation won that game.

Image source, Getty Images

After a confident start from Roman Safuillin, the game ends with a break of serve for Novak Djokovic.

First point of the match, Novak Djokovic manages to return the qualifier's volley at the net but Safuillin hammers an overhead winner.

Another forehand winner follows but a couple of more nervy shots gives Djokovic a break opportunity and he gets it when Safuillin hits a forehand limply wide.

That's more like it from Iva Jovic as she comes through a service game with much more confidence, darting around the court and polishing the game off with a neat volley at the net.

This has been a scrappy match in the early stages and it's been waiting for someone to grasp control of it.

Jovic just does that as she brings up three break points and breaks to love as Jessica Pegula goes tamely into the net.

Jovic to serve for the set.

Warm-ups almost done so we're just a few short moments away from the first match of the day on Centre Court.

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

Roman Safiullin has definitely earned his right to be here. He has played three five-setters in a row and come through three final set tie-breaks to get here.

He put on an amazing performance against Joao Fonseca, who many would have fancied to beat him. He has nothing to lose. He is playing with playing with house money. You could see how much it meant to him with all the emotion to get through that last match.

Let's hope he gets out there and gets after the ball.

Image source, Rex Features

Both players are struggling to hold serve at the moment with three successive breaks of serve.

I wonder if the sun is making it difficult for the serving players?

Jovic faces pressure again with the ball hand as she is taken to deuce, before planting a forehand into the net as Pegula seals a fourth straight break between the players in this first set.

Ask Me Anything

There is a total prize fund of £64.2m at Wimbledon this year, a figure that is split between all rounds of the competition. Also included in that figure is money won by players in the men's and women's singles that entered via qualification.

Here is how much singles players who are still in the draw stand to earn.

• Exit in fourth round: £300,000
• Exit in quarter-finals: £480,000
• Exit in semi-finals: £900,000
• Runner-up: £1,800,000
• Winner: £3,600,000

Harry Poole
BBC Sport at Wimbledon

The two men's matches on Centre Court are true David v Goliath showdowns.

Neither seven-time Wimbledon champion Novak Djokovic or reigning champion Jannik Sinner have ever lost a Grand Slam match to players ranked as low as their opponents today.

Those opponents, qualifiers Roman Safiullin and Shintaro Mochizuki, pulled off huge upsets to get to the fourth round - but few would give them a chance today.

Should either world number 132 Safiullin or the 151st-ranked Mochizuki win, they would become only the sixth qualifier to reach the men's singles quarter-finals at Wimbledon in the Open Era.

If both men beat the odds and oust Djokovic and Sinner, it would be the first time in the Open era that multiple qualifiers have reached the last eight at a Grand Slam.

It's going to be a remarkable day if that is to happen.

Roman Safiullin is going to have to rely on his forehand if he is to trouble Novak Djokovic today.

This is the fourth time these two have met on court, with Djokovic holding a 3-0 head-to-head record over the Russian.

Safiullin has lost all three of those ties in straight sets, though he's never played the Serb at a Grand Slam before.

Harry Poole
BBC Sport at Wimbledon

Image source, Getty Images

It's another star-studded line up in the Royal Box today, with sporting royalty here to enjoy Sunday's action.

Everywhere you look there are medal winners and record holders.

Olympic triathlon champion Alex Yee, former England cricket captain Andrew Strauss, former marathon world record holder Paula Radcliffe, winners of multiple Olympic track cycling golds Laura and Jason Kenny, rugby World Cup winners Sadia Kabeya and Megan Jones.

Jessica Ennis-Hill, Kelly Holmes, Jonathan Edwards, James Anderson, Matt Dawson, Danny Care... I could go on and on!

A bit of pressure on the tennis players to put on a show for this audience today.

Image source, Getty Images

They were given a bit of a scare but Henry Patten, of Britain, and Finland's Harri Heliovaara - the top seeds in the men's doubles - have battled through to the fourth round.

They found themselves a set down to Czech pair Adam Pavlasek and Patrik Rikl, then a break down in the third set, but fought back to win it in the deciding 10-point tie-break.

We're under way on Court One and Jessica Pegula has faced some early pressure from fellow American Iva Jovic.

After saving one break point, fourth seed Pegula couldn't rescue the second as she went long with a backhand.

Following Elena Rybakina and Iga Swiatek's exits on Saturday, Pegula is the second-highest seed remaining in the women's draw after top seed Aryna Sabalenka.