Waiting in round four for the winner of Johanna Konta's match is world number 48 Anastasija Sevastova. She's in fine touch.

A forehand reply is long for Belinda Bencic and she resembles a car which has run out of fuel, there's not half an hour gone.

That leaves Johanna Konta with set point on serve. The first is long, the second isn't and guess what, Bencic is long again. Her radar is some way off right now, Konta takes the set in 28 minutes.

Image source, Getty Images

Leon Smith
Great Britain Davis Cup captain on Radio 5 live sports extra

The Bencic serve is not doing any damage. She isn't getting enough first serves in, which means Konta is getting a lot of chances to attack the second serve and rip into her returns.

Some magic from Johanna Konta to crack a backhand down the line and level at 30-30. The body language of Belinda Bencic is now negative, almost stroppy as the ball passes her.

Konta is sensing it you feel, she jumps to get over a forehand and just lashes it across court to set up a break. She has momentum, this will go her way will it? Too right, another winner, this time down the line and the shoulders of Bencic sink.

Serving for the set next.

Image source, .

305. 153. 112. 150. 47. 14.

Notice a pattern? That's how Johanna Konta's world ranking has improved at the end of each year starting in 2011 and culminating in her position at 14 for this tournament.

In January, she became the first British woman in 32 years to reach a Grand Slam semi-final, after defeating China's Zhang Shuai at the Australian Open.  

With such improvement comes expectation and pressure. Today she's handling it well so far.

Leon Smith
Great Britain Davis Cup captain on Radio 5 live sports extra

Konta is not expending any energy on her serves. She's serving very smartly, to the Bencic forehand and has had some cheap points.

At 40-15 on her serve, Johanna Konta has won nine of the last 10 points. Make that 10 from 11 as she lamps a serve up the middle and the backhand from Belinda Bencic is 10ft over the baseline.

I did just say Belinda Bencic was making her service games look harder than a day down a coal mine. 

A double fault does little to settle her down and Johanna Konta pounces. Bencic flops a return into the net and that was lame all over. A big break for Johanna Konta who bounces on the spot ahead of her next service game. She looks positively pumped by that serving disaster for her opponent.

The most comprehensive display of serving we have seen in the match so far. Johanna Konta doesn't look threatened as she targets the forehand of Belinda Bencic a few times.

It's great work, punctuated by a 94mph ace to lead 40-0. A quick-fire game. Konta cruising on her service games with the roof down on Route 66. Bencic slugging away on her serve like a driver on Ice Road Truckers.

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Seems like yesterday we used to rock the show

I laced the track, you locked the flow

So far from hangin on the block for dough

Notorious, they got to know that.... 

Image source, Faith Evans

Why the brief injection of 'I'll be missing you' by Puff Daddy?

Because when we last had four Britons in round three of a Grand Slam, he - alongside Faith Evans - topped the UK charts with this classic number.

Shout out to those people who recorded the charts on cassette in 1997. 

Leon Smith
Great Britain Davis Cup captain on Radio 5 live sports extra

It's a really good match. Very quickly both players have found their timing. It's high quality tennis.

Johanna Konta off to a flyer in the third to set up two break points. 

Here comes the first, a long return and that's one gone. Now a rally at 30-40, both players in control and pinging balls back and forth as they await an opening, Konta gun slings first but that's wide by probably an inch, deuce.

Belinda Bencic has her rival on the run and will smash this ball away for advantage will she? No... back it comes but the Swiss converts from the centre of the court to wrong-foot Konta. This game is a cracker and Bencic picks up a drop shot with Roger Federer-esque style, that's gorgeous and it's rewarded as Konta goes long on the next point.

We remain on serve. A chance wasted for the Brit.

Image source, Getty Images

Leon Smith
Great Britain Davis Cup captain on Radio 5 live sports extra

Konta definitely has more power and the bigger groundstrokes so should hit more winners, but Bencic puts the ball in awkward areas, moves players around the court and can draw errors from opponents.

Johanna Konta is now perhaps at a level where we expect to see dominance, clear service games, little fuss, ruthless when it matters. That's the name of the game at the top of world tennis, eat or be eaten.

A lovely dip on her backhand allows her to leave Belinda Bencic wanting, securing a 40-15 lead and then kaboom, an ace right up the T levels the boards.

Image source, Getty Images

A double fault from Belinda Bencic puts her 15-30 down on serve early in the opener, some jitters?

A strong forehand into the corner tells us that's not the case and Johanna Konta hustles but her stretching backhand can't clear the net. 

Bencic steps it up and even has time for a little fist clench as a Konta return floats wide to secure the opening game.

The new Grandstand court looks a picture but the crowd inside is sparse for now as the sub shines from a sky well populated with fluffy white clouds in New York.

The formalities and warm up is done and dusted, it will be Belinda Bencic to serve. She adjusts her ponytail a little, she's gone for a peach visor while Johanna Konta is sporting a white one. Whatever happened to a traditional peak cap?

Image source, EPA

Leon Smith
Great Britain Davis Cup captain on Radio 5 live sports extra

Belinda Bencic is a great talent, and obviously gets compared to Martina Hingis a lot, not just because she's Swiss but because she has great technique and hand skills.

Her current ranking is not a true reflection of her ability.

Image source, Getty Images

What do we know about Johanna Konta's rival on this glorious Friday evening?

Belinda Bencic is coached by the mother of Martina Hingis. She ought to know a thing or two about tennis.

Bencic has two WTA Tour titles to her name, that's one more than Konta. And the head-to-head is also 2-1 as the Swiss player overcame Konta in Eastbourne last year and in Acapulco a year earlier.

Image source, Getty Images

Johanna Konta and Kyle Edmund will bid for fourth round places this evening. There will be intense focus on Konta after her difficulties in the second set of her second round win of course.

"It was a bit of a shock to the system what happened," she said after her deciding set win. 

"Basically my heart rate just shot up and so did my breathing and control of my breathing. I started shaking. 

"It's not a position any athlete or person would want to be in. It's quite shocking to the system and very personal in front of so many people. It's a little bit embarrassing."

Johanna Konta is warming up with Belinda Bencic. Is her mind clear of a traumatic experience?