Oh dear.

What happened there? Konta looked a bit shaky in that game and it gives Vekic the chance to break back.

Konta's forehand goes wide and it's break point Vekic.

Konta's first-serve percentage was up at 77% at the end of the first set. It's now 66%.

She's not quite up at the level she was playing in that first set and it's back to deuce again.

Konta faults on her first serve and hesitates before taking her second. Is doubt creeping into her mind?

Maybe not, she whacks a backhand and is serving for the game again.

Vekic comes out firing. She slams a backhand and it lands on the baseline. Deuce.

It looks as though Konta has hit a forehand winner, but wait! It's out. The umpire comes down to check... Nope, still out. 30-40.

The fans who are there are getting behind the Brit, though. They clap as she serves for the game.

Konta misses her first serve on the first two points, but makes amends with an ace. Two points from a 5-3 lead in the second set.

She is enjoying her most successful French Open ever, but there still aren't many people there to see it on Suzanne Lenglen.

Naomi Cavaday
BBC Radio 5 live tennis commentator at Roland Garros

Johanna Konta has maintained such a high level through the match, she is settled and has purpose and intent. She looks so calm. Even when she was up at world number four in 2017, it was great when she was in the groove, blasting people off court, but it did also look a little frantic.

Image source, Getty Images

She's done it! Vekic hits another ball long and Konta breaks.

She just needs to hold serve twice more (or, dare I say, hold and break!) to make it into her first French Open quarter-final.

Konta sends Vekic running right and the Croat can't quite get round the ball. She hits it long and it's break point Konta.

Woah. Konta is deep behind the baseline but hits a gorgeous backhand winner, which just lands in.

Another cry of "come on" comes from Vekic as she evens things up at 15-15.

Image source, Getty

Incoming to Court Philippe Chatrier is his Royal Swissness, Roger Federer.

The 20-time Grand Slam champion is taking on Argentina's Leonardo Mayer today for a place in the last eight.

He has won all three of his previous meetings with the world number 68.

Same again?

Konta puts in a speedy second serve, but hits the next ball long. This service game might not be as simple as it looked initially...

Oh wait, Konta hits another ace. She holds.

Smart play from Konta. She's mixing things up on every point.

The Brit double faults to give Vekic a look-in, though. 15-40.

Apparently Petra Martic has a glass of red wine every time she wins. I could get on board with that.

Image source, Getty Images

Donna Vekic's fellow Croat Petra Martic is into the last eight.

She came from a set down to beat Estonia's Kaia Kanepi 5-7 6-4 6-2. She will play Czech teenager Marketa Vondrousova in the quarter-finals.

Konta decides to liven things up as she takes a 30-0 lead on Vekic's serve.

The Croat quickly levels things and Konta blinks first in a lengthy rally, hitting the ball long.

Vekic holds as the clock reaches an hour.

Image source, Getty Images

Jonathan Jurejko
BBC Sport at Roland Garros

Jo Ko completely trusts her game at the moment. That’s illustrated when she puts away another crunching forehand in that comfortable hold, increasing her tally of winners to 20.

Konta hits a backhand winner, then follows it up with an ace and a forehand winner.

The Brit makes an error, hitting the ball long, but it's still a straightforward hold.

This is a far cry from the start of the first set, when people were breaking serve all over the place.