Raducanu absorbs the pace on a Vekic forehand with her legs and finds the corner with a great return.

Vekic hits back twice to go in front, before Raducanu hits a beautiful backhand winner from a powerful Vekic return. She is turning Vekic's power against her.

Raducanu then spoons a shot to give Vekic the chance to smash, but the Croat clips the net and the ball drops into the tramlines.

Annabel Croft
Former British number one on BBC One

Raducanu is doing a great job getting Vekic on the run, hitting into open space and moving her around.

She was getting a bit rattled talking to her coaching team but she is now starting to change the rhythm of the match and I think Vekic is feeling the pressure a bit and missing a few more first serves.

Emma Raducanu breaks and leads for the first time today!

The Brit is coping much better with Vekic's serve, and brings up two break points with a superb forehand winner down the line.

But Raducanu then goes long on a return, then misses a drop shot. Deuce.

Vekic nets at the end of the longest rally of the match to bring up a third break point, and Vekic nets and hits her racquet on the court in frustration.

That could be a huge break.

Image source, Getty Images

Annabel Croft
Former British number one on BBC One

That's a big crowd reaction. It will be interesting to see how Vekic handles the energy of the crowd right now.

Jonathan Jurejko
BBC Sport tennis news reporter at Roland Garros

The huge roar from Raducanu at finally getting on the board is quickly drowned out by the reaction of the crowd.

Raducanu is suddenly grinning and has a spring in her step.

Is the fightback on? It's one small step on a long road ahead.

Emma Raducanu is on the board.

Some heavy-hitting serves from the Brit force Donna Vekic off her stride.

The crowd erupts - is the comeback on?

Is Donna Vekic dropping off a bit?

The Croat nets a return and then fires the ball out, so Raducanu is 40-0 up.

Donna Vekic makes light work of the first game of set two, with Emma Raducanu struggling with her opponent's power.

Raducanu is frustrated - she turns to coach Andrew Richardson and says: "Say something, you're saying nothing."

Annabel Croft
Former British number one on BBC One

Vekic has played a set of tennis of sheer brilliance and motored her way through it.

Raducanu has been totally overwhelmed by the power. Donna's returns have been unbelievable and have not allowed Raducanu to play her game.

Image source, Getty Images

Emma Raducanu got just 47% of her first serves in during that first set, compared to 59% for Vekic.

Vekic won 92% of her first serve points, Raducanu just 50%.

Raducanu nets another first serve, and then nets after Vekic returns her second serve. Set point Vekic.

A long rally follows, and eventually Vekic takes the set with a great shot down the line to Raducanu's right.

What a set for Vekic.

Annabel Croft
Former British number one on BBC One

Raducanu needs her first serve to be firing.

Donna Vekic produces a fine backhand drop shot that catches Raducanu out, but Raducanu's next serve is too powerful for the Croat to return.

30-30.

Raducanu forces Vekic to the back of the court before coming to the net and taking the point.

She then double faults for a second time today. She can't afford too many more of those.

Jonathan Jurejko
BBC Sport tennis news reporter at Queen's

As I suspected before the match, Raducanu is not quite up to the mark physically.

She is not pushing off her left leg as explosively as previously this week when she is defending, while does not seem to be able to get as low down to her groundstrokes.

Vekic pummelling the ball and painting lines with winners isn't helping her cause, mind.

The British crowd has somewhat had the wind taken out of its sails. All a bit flat.

Emma Raducanu has called for the trainer - it looks like she wants to remove the heavy strapping on her left thigh.

Annabel Croft
Former British number one on BBC One

When your opponent makes a fast start you have to try to slow down the pace of the match between points, or throw in more slices to take away the rhythm of your opponent.

Emma is definitely being rushed on her strokes today.

A clever slice from Raducanu forces Vekic to net, but Raducanu then returns long to give Vekic game five.

Annabel Croft
Former British number one on BBC One

This is clinical from Vekic. She is mixing her serve up well so Raducanu doesn't know what's coming next.

Donna Vekic is playing some clinical shots.

A big serve has Emma Raducanu scrambling, before Vekic produces a pin-point shot into the opposite corner.