Emma Navarro's playing with so much more aggression now and it's paying off.

The American breaks back to put us back on serve in this second set.

A big serve down the T clinches a comfortable hold for Ben Shelton.

The American 10th seed is showing no signs of letting up after his impressive showing in the third-set tie-break.

Gary Rose
BBC Sport at Wimbledon

There's more people in their seats now, perhaps drawn in by the oohs and ahhs that followed that amazing first-game rally that ended with Mirra Andreeva getting an immediate break. Emma Navarro must be wondering what she has to do to beat the teenager.

Oh my goodness.

Mirra Andreeva, that is phenomenal.

The Russian was 30-0 down but wins three points in a row to earn the break point.

The longest rally of the match follows, with Andreeva spending most of it defending against the aggression of Emma Navarro.

But the teenager turns defence into attack to hit a cross-court forehand winner for the break.

A very telling stat has just flashed up on BBC coverage.

Lorenzo Sonego has a 6-32 record against top 10 players. He has lost his past 14 such encounters.

The Italian needs to win the next two sets to halt that sequence - he takes Ben Shelton to deuce to start set four but is fuming after a backhand goes long and the American goes on to hold.

Jonathan Jurejko
BBC Sport senior tennis reporter at Wimbledon

Image source, Getty Images

One is a chatty 18-year-old long tipped as a future Grand Slam champion.

The other is a straight-talking 53-year-old former Wimbledon winner, who has also coached another top player to the title.

Together, Mirra Andreeva and her coach Conchita Martinez are forming a successful double act.

"Mirra is a very special player and very complete in everything she does – but also improvable. I think she has a lot to learn," said Spaniard Martinez, who memorably won the 1994 title.

"If I won Wimbledon - I was more of a clay-court player - then I think she has a good shot of winning."

Read more about the blossoming partnership which Andreeva and Martinez hope will lead to the Wimbledon title.

Image source, Reuters

Is there an obvious weakness to Mirra Andreeva's game?

The Russian had the most difficult service game of the set there and Emma Navarro earned a break point.

But the teenager fires off a 119mph serve that Navarro can't return to take it back to deuce, before holding to take the first set.

She showed a bit of everything in that set, dictating from the baseline and overpowering Emma Navarro - who was broken twice.

You can see why many are tipping her as a future Grand Slam winner.

Marion Bartoli
Former Wimbledon champion on BBC Radio 5 Live and BBC Sounds

I would like Emma to change up a bit from the back of the court rallies, bring Mirra a bit more forward and giving her different angles. Even though you might lose the point, it's still change up. You don't want to stay in the same tune all the time.

Martina Navratilova
Nine-time Wimbledon singles champion on BBC Two

Andreeva does so well and takes the ball on so quickly. She is fast around the court and reads the play really well.

You can have all the talent in the world but you need to have the determination too. She is the whole package and is still just getting started. Conchita Martinez has backed a good horse.

Ben Shelton was virtually flawless in that tie-break, anticipating everything that Lorenzo Sonego threw at him.

He shares a satisfied look with his friends and family at courtside after a stunning backhand return lands on the baseline to seal an emphatic breaker in which Sonego won just one point.

The 10th seed a set away from a first Wimbledon quarter-final.

Laura Robson
Former British number one on BBC Radio 5 Live and BBC Sounds

Image source, Getty Images

The error keeps coming off Navarro's forehand. It's almost like her body stays too far behind her when she is making contact with the ball, which maybe isn't a technique you would teach. It looks a bit uncomfortable, and like she is playing with the wrong grip at times.

When she has time it works perfectly, but when she is being pressured it looks like she has to think so much before she plays the shot.

Martina Navratilova
Nine-time Wimbledon singles champion on BBC Two

Navarro is trying to keep the ball low but it is tricky when you are so far behind the baseline.

Andreeva has got a lot more pop on her serve now. If Navarro keeps her positioning close to the baseline, Andreeva will be dictating the whole match.

Navarro is losing power on her serve because she opens her body up too early so it is all coming from her arm. She needs to use her body more.

Image source, Reuters

Much better from Emma Navarro, who holds to 15.

Mirra Andreeva will come out to serve for this first set after the change of ends.

Jonathan Jurejko
BBC Sport senior tennis reporter at Wimbledon

Like many teenagers, Mirra Andreeva is still prone to a tantrum or two.

Some of her behaviour - notably swiping away balls towards the crowd - has come close to crossing the line.

The way she combusted against home wildcard Lois Boisson in a febrile French Open quarter-final last month was also a reminder of her tender years.

In her first appearance on Centre Court, she is looking calm and collected so far.

Laura Robson
Former British number one on BBC Radio 5 Live and BBC Sounds

Both players are incredible movers, Andreeva in particular. For me, she is right up there just behind Coco Gauff as one of the most fluid movers on the court.

She is recognising the patterns of play so far and getting herself in the right positions. She has more 'oomph' on her forehand compared to her opponent, so it is a tricky challenge for Emma Navarro.

Gary Rose
BBC Sport at Wimbledon

Mirra Andreeva is bouncing around the court and dictating things from the baseline like she has played on Centre Court all her life.

We're only 23 minutes in and she's one game away from taking the first set. So far, a dominant display by the teenager.

"Come on," yells Ben Shelton, as a Lorenzo Sonego shot goes long. He repeats the exclamation when the same thing happens the next point.

And then the American basks in the Court One applause when he stretches every sinew to reach a backhand volley that puts him three points to the good in the breaker. Make that four, as another Sonego forehand flies out.

Mirra Andreeva is hitting it out there like it's her 100th appearance on Centre Court, not her first.

The Russian eases to her third consecutive hold of the set.

Ben Shelton looks in trouble at 0-15 when his first serve finds the net - but a second serve at 116mph right into the Sonego body gets him back on parity. Gamble but, boy, did it pay off.

A big forehand winner down the line seals the hold and we're going to a tie-break.

Image source, PA Media

Mirra Andreeva's power is proving too much for Emma Navarro to handle right now.

Once they get into a hitting match from the baseline, there's only one winner.

The Russian seventh seed has a commanding double-break lead.