I was just about to say the variety had gone from Varvara Gracheva's game but she ramps up the spin on her second serve to force an error from Aryna Sabalenka.

However, following it with a double fault is not part of the plan and she finds herself fending off two break points once again.

One backhand slap into the net later and Sabalenka edges ahead.

Alexandre Muller saves another break point with an unreturnable serve, and he follows it up with another - but it's deemed out.

He gets the advantage next time round with a forehand volley.

But...Alcaraz finds the line and we're back to deuce.

Paula Badosa was congratulated on her 'win' in her post-match press conference, after she was forced to retire from her second-round match against Ukraine's Marta Kostyuk.

I think she handled this rather well...

A stunning sliced forehand gives Carlos Alcaraz the advantage but Alexandre Mulller isn't letting him get away with it that easily and pulls us back to deuce.

The biggest cheer of the day goes to a ball kid who manages to catch a wayward ball coming from quite a height.

Muller can't capitalise on two advantage point as an Alcaraz drop shots forces the fourth deuce of the game.

A fifth ace of the game gets Sabalenka's serve rolling and she follows it up with a too-hot-to-handle forehand into the back corner.

Another ace follows - her eye is definitely in - and she shrieks with delight as she rattles another forehand winner to seal the game.

A looping lob helps Alcaraz to a 0-30 lead.

However, Muller saves two break points and forces deuce, with two challenges going against the top seed.

Varvara Gracheva looks a bit weary - did we mention how hot it was? - and she puts two forehands into the net to kick off the third set.

She hits the chalk skilfully twice in quick succession but is unbalanced with a backhand and suddenly it's two break points for Aryna Sabalenka.

You feel this is an important game for both players though and Gracheva digs deep to save the break.

She holds. Impressive comeback.

Jess Anderson
BBC Sport at Wimbledon

I just wonder if Sabalenka is struggling somewhat with the heat. At every change of ends she has been touching her face, neck and shoulders with a bag of ice.

A bit of a shift in momentum now, though - can she put her foot down to come through this wobble?

In other news, I just nearly got hit on the head by a flying champagne cork. Just love Wimbledon.

Alcaraz races through his service game to hold to love. The Spanish top seed is finding his rhythm.

An ace from Muller gets us underway in the second.

A fantastic rally ends with an overhit passing shot from Alcaraz and Muller holds after the top seed hits an unforced error into the net.

Michael Emons
BBC Sport at Wimbledon

A clenched fist from Alcaraz and after a thoroughly enjoyable opening 45 minutes, he takes the first set.

The second set starts as the first one ended, with packed stands on Centre Court. No-one wants to leave this one, and no wonder why.

For Muller, those three break points missed when it was only 1-2, will show him he can get at Alcaraz.

But in the end Alcaraz's break in game seven proves the difference.

Aryna Sabalenka won 95% of points on her first serve in set two and that was the difference.

It's tough to bet against her going on to win this one now.

A chink in Sabalenka's service armour on the first point of this game but she swiftly dispels that with two whipped forehand winners.

A thumping serve brings up two set points only for a fine return from Gracheva to leave the Belarusian scrambling.

However, Gracheva goes long with her next shot and Sabalenka duly levels things up.

Image source, Getty Images

Let's have a sweep around the courts and bring you right up to date with everything that's currently going on away from the two main showcourts at the All England Club.

• Italian Matteo Berrettini is about to serve for a straight-set win over Australian 15th seed Alex De Minaur on court 18, leading 6-3 6-4 5-4.
• On court two, 19th seed Alexander Zverev is a set to the good against Japan's Yosuke Watanuki.
• Over on court three, Italian eighth seed Jannik Sinner has not long been under way against Frenchman Quentin Halys, but he has suffered an early break of serve.
• British pair Heather Watson and Harriet Dart have also just started their women's doubles campaign against Jelena Ostapenko and Lyudmyla Kichenok.
• And out on court 17, men's doubles top seeds Neal Skupski, of Great Britain, and Dutch team-mate Wesley Koolhof have raced into a 4-1 lead over Aslan Karatsev and Daniel Altmaier in the first set.

And he gets it. Alcaraz takes the opener 6-4 with Alexandre Muller hitting another unforced error.

Can the Frenchman make more of an impact in the second set? Or will Alcaraz's momentum continue?

An unexpected drop shot catches Muller off guard as Alcaraz takes a 30-15 lead.

The French world number 84 starts working Alcaraz around the court but he overhits a forehand to give another two set points to the top seed.

Michael Emons
BBC Sport at Wimbledon

Great character from Muller to fend off three set points for the Spaniard after some exquisite shot-making from the world number one.

A lovely cushioned crouching volley at the net, a superbly-weighted drop shot and a stunning forehand from Alcaraz were all beautiful to watch, yet they aren't even enough to give him the game.

Muller hangs in there, fights hard and keeps the set alive with an ace.

He now has to break Alcaraz's serve though with the 20-year-old serving for the set.

Has the momentum shifted?

Aryna Sabalenka is hitting the court with her groundstrokes and finally putting Varvara Gracheva under pressure.

The Frenchwoman caves in the face of some heavy hitting - and Sabalenka has an important break.

Three set points saved by Alexandre Muller in that game and he gets over the line with an ace.