Muller's break point comes and goes in an instant as he's unable to return a pacey Alcaraz serve.

Once more we go to deuce.

Once again Alcaraz is unable to capitalise on an advantage point with another unforced error.

Another deuce.

Sealed with an ace.

The world number two was scrambling in the first set here but found her form and moved through the gears in sets two and three.

Sabalenka moves on to face 24-year-old Russian Anna Blinkova in round three.

Despite making his Centre Court debut, Alexandre Muller is certainly relaxed as he coolly catches a ball straight into his pocket.

And he has a break point as Carlos Alcaraz hits a drop shot into the net.

Aryna Sabalenka appears to be powering towards victory on Court One, so that means it might not be long before Cameron Norrie is in action.

He is second on that court, taking on American Chris Eubanks.

Norrie is one of a number of Brits in action today with Andy Murray of course resuming his match against Stefanos Tsitsipas on Centre Court after the Alcaraz-Muller tussle.

After that there's more top tier clashes on Centre, with women's number one Iga Swiatek taking on Petra Martic before seven-time champion Novak Djokovic goes up against Stan Wawrinka.

Meanwhile, on court two, British number five Liam Broady is up next against Denis Shapovalov.

Twelve break points saved by Varvara Grecheva in this match but ruthless efficiency from Aryna Sabalenka stops it becoming 13 - and this could be done now.

The world number two has finally ground down her French opponent and she will have two opportunities to serve for the match.

Alexandre Muller hangs on once again as Carlos Alcaraz overhits a backhand.

We remain on serve as it stands. On we go...

Alexandre Muller races to a 40-0 lead in his service game.

But Alcaraz grabs the next three points to force deuce.

Scratch that.

Aryna Sabalenka finds the two first serves when she needs them and holds.

A bit of resistance from Varvara Gracheva as she tries to find that break.

Aryna Sabalenka hits two big serves for points but Gracheva hangs tough to bring up 30-30.

She overturns an ace but then is beaten by the second serve. Sabalenka again misses with her first serve and then goes long.

At deuce, Gracheva is threatening.

Oops, maybe I spoke too soon that Alcaraz's drop shots were working. Alexandre Muller somehow returns his serve but the Spaniard's drop shot, which he had lots of time to execute, finds the middle of the net.

The pair exchange unforced errors before Alcaraz holds with a one-two serve-volley.

There are more Brits in doubles action at the moment and it's going well so far.

Men's top seeds Neal Skupski and Dutch partner Wesley Koolhof have taken the first set 6-3 against Daniel Altmaier and Aslan Karatsev.

In the women's event, Heather Watson and Harriet Dart have just wrapped up the opener 6-4 against the seventh seeds, Jelena Ostapenko and Lyudmyla Kichenok.

Michael Emons
BBC Sport at Wimbledon

A lovely baseline rally and the luck is on Carlos Alcaraz's side as the ball flicks off the tape, instantly loses all its pace and dribbles over the net with Alexandre Muller left with his hands on hips looking helpless.

But the tennis gods instantly redress the balance with Muller getting his own luck with a net cord a few shots later, before a couple of stunning serves from the Frenchman ensure the hold.

After 75 minutes we're probably not even halfway through the second set, with Andy Murray, Iga Swiatek and Novak Djokovic all still to come, it's going to be a very busy, dramatic and long day.

If you've got Centre Court tickets today, you've absolutely had a stroke of great fortune.

Great match, great weather, great times.

CoCo Vandeweghe
Two-time Grand Slam semi-finalist on BBC Radio 5 Live

When you are playing Sabalenka the ball can't be coming at the same place all the time. You have to change what the ball looks like.

You can't be a hitting partner for the big hitters.

Poor Alexandre Muller. He was looking good in a lengthy rally but a Carlos Alcaraz return clips the net and falls onto the Frenchman's side.

But he gets his revenge with two deft winners that send the Spaniard flying and he finishes the game off nicely with an ace.

A chance for Varvara Gracheva to take the game? No, as Aryna Sabalenka bites back with a ferocious forehand.

Another fine serve brings up game point again and this time she clings on.

She'll still need to find a break if she's going to get back into this.

More like it from Varvara Gracheva who approaches the net for the first time this set and closes the point with a well-executed backhand smash.

You feel she needs to do more of that though as she gets embroiled in two rallies from the back of the court and there's only one winner of those.

At 30-40 though, Gracheva digs out the body serve and we're at deuce.

Carlos Alcaraz is starting to bring out the drop shots now and make Alexandre Muller come to the net. It's working as he takes a 30-15 lead.

But the pair are on level terms again after two errors from the Spaniard.

Muller is unable to return an Alcaraz second serve as the top seed holds to keep the second set on serve.

Michael Emons
BBC Sport at Wimbledon

One of the best games of a high-quality match as Alcaraz, showing a superb touch and weight of shot, gains a couple of break points after two successive challenges, one going against him, one going for him.

But he wastes one of the chances as he flicks the ball wide and then goes into the net with the second opportunity.

Alcaraz then gives hope to club players everywhere by completely getting a shot wrong. The ball flies high, high into the air and it's so high it would've hit the roof if it had been closed. A ball kid is under it, can he catch it...yes he can after a bit of a juggle. Well held and a warm round of applause for his effort.

Another break point is seen off by some superb serving from Muller and the lengthy game goes the Frenchman's way, just about.

There's a chance at 0-15 for Varvara Gracheva but her radar is off and she goes long with a forehand.

Aryna Sabalenka takes advantage with two powerful serves and squeezes her opponent into the corner with a backhand.

These service games are proving straightforward now.

Alexandre Muller gets the 10-minute game over and done with. A good hold for the Frenchman.