Russell Fuller
BBC tennis correspondent on BBC Radio 5 Live

Emma Raducanu seems to be relieved. It wasn't an entirely convincing game, she didn't look confident, but she's held serve.

On the board! Emma Raducanu goes again, winning back-to-back points from 30-30 to get her first game. That will be a big relief.

But that won't... A double fault follows from Emma Raducanu - and now she has some crucial points coming up.

No sign of any momentum change in the opening point of set two as Solana Sierra immediately puts Emma Raducanu on the back foot and forces a miss from the Briton.

But there is a first winner from Raducanu! A forehand beats Sierra. That will feel good.

Jonathan Jurejko
BBC Sport tennis news reporter in Paris

"Nice weather. Bit hot though."

A classic British exchange between two fans exchanging pleasantries outside the court where Raducanu is playing.

The mercury is up to 31C. It’s warm but not that warm for the players, who are used to playing in such conditions.

Humidity is not high and a gentle breeze is cooling, too.

Fans behind the baseline giddily whoop, though, when they are sprinkled by the water being hosed into court while we wait for Raducanu to return.

Annabel Croft
Former British number one on BBC Radio 5 Live

It was quite extraordinary to witness that.

Even though I think Raducanu is rusty and low on confidence, I've never seen her play a set of tennis like that. Breaking down so early, wasn't able to extend the rallies in anyway at all and overpowered at the back and lost all her confidence on the swing.

I've never seen her hit the balls halfway up the net, missing shots wide, missing shots long - no confidence in how to get the ball in the court.

Can Emma Raducanu reset here?

The crowd are enjoying a bit of a freshen up as a member of staff sprays a hose at those who need cooling down after spending the day in the intense Paris heat.

Raducanu left the court at the end of the first set and returns to warm applause.

Annabel Croft
Former British number one on BBC Radio 5 Live

She looks so subdued. It doesn't look like her. Raducanu is usually so energetic.

Jonathan Jurejko
BBC Sport tennis news reporter in Paris

Raducanu’s body language is not great. To put it mildly.

Pre-tournament, she seemed focused on the practice courts and jovial with the media.

Now, understandably, she is head bowed with a sullen expression between points.

No idea how she turns things around on the basis of what we have seen so far.

Image source, BBC Sport

13 unforced errors and counting for Emma Raducanu as Solana Sierra moves within a couple of points of serving up a first-set bagel.

Another miss from the Briton gives Sierra set points, and Raducanu sends a final backhand into the tramlines to end a poor first set.

The first set is gone in just 24 minutes and Raducanu is yet to enter the contest.

Fran Jones is back on serve!

After conceding early in the decider, the Briton settles down and then strikes to square things up at 2-2.

Another hold of serve nudges her in front.

Annabel Croft
Former British number one on BBC Radio 5 Live

Raducanu looks so lacking in confidence. I've never seen her break down this early in rallies.

You might see her putting in some unforced errors if she's under pressure but she's breaking down on the third strike of the rally which is unusual.

She can't find the court at all.

This first set has got away from Emma Raducanu so quickly.

The British number one makes a first serve to save a break point at 15-40, but Sierra lands a return to take her second opportunity.

The scoreboard makes for pretty tough reading for Raducanu after 21 minutes.

Jonathan Jurejko
BBC Sport tennis news reporter in Paris

Sierra looks like the player who has more rhythm and better timing.

Not surprising given how much she has played compared to Raducanu this season - and particularly on the clay.

Sierra - who pushed Coco Gauff in Rome, remember - has 12 clay-court matches in the bank, while Raducanu is playing only her second match on the red dirt.

Annabel Croft
Former British number one on BBC Radio 5 Live

I think this is one of the lowest level starts I've seen from Raducanu. I think she'd almost say it herself.

I've not seen this many errors from her in a match.

Image source, Getty Images

Russell Fuller
BBC tennis correspondent on BBC Radio 5 Live

Raducanu has a very good record in the first round of Grand Slams. She's only lost two of the 15 matches she's played.

She shouldn't be written off quickly but given she's played little tennis in the clay season, it does count against her.

It feels a 50-50 match at best, even though Raducanu is 29 places higher in the rankings.

Solana Sierra finds her rhythm again and levels at 30-30 with a backhand winner, but Emma Raducanu makes her way to deuce to keep herself involved.

The Briton gets a break point but the opportunity passes as she misses her backhand and Sierra manages to escape.

Emma Raducanu needs to gain a foothold quickly here and she gets some encouragement as she takes the opening point on Solana Sierra's serve.

The Argentine misses a backhand - and now this is a genuine opportunity for Raducanu to get back into this.

Annabel Croft
Former British number one on BBC Radio 5 Live

It's going away quite quickly and Raducanu looks hesitant in the way she's swinging at the ball, like she doesn't trust herself and isn't confident. I think Sierra is sensing that at the other end.

I think it comes down to that lack of match practice.

Image source, Getty Images

Russell Fuller
BBC tennis correspondent on BBC Radio 5 Live

Not what Emma Raducanu would have been hoping for...