Video Assistant Refereepublished at 53 mins
Barcelona 0-1 Chelsea
Mariona Caldentey is standing over the ball - but the decision is being checked by the Video Assistant Referee...
Summary
FT: Barcelona 0-1 Chelsea - Erin Cuthbert scores only goal with brilliant, composed finish
Hosts have second-half penalty overturned by VAR
Barca suffer first competitive home defeat since February 2019
Second leg at Stamford Bridge on 27 April
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Video Assistant Refereepublished at 53 mins
PENALTY TO BARCELONApublished at 52 mins
Barcelona 0-1 Chelsea
Gut punch for Chelsea.
Patricia Guijarro's shot from distance smacks into the arm of Kadeisha Buchanan, and Stephanie Frappart points to the spot.
Image source, Getty Images'Chelsea not allowing Barcelona to smother the game'published at 13:38 British Summer Time 20 April
Barcelona 0-1 Chelsea
Pat Nevin
Former Chelsea and Scotland winger on BBC Radio 5 LiveWhat Barcelona want to do is get the ball, pass it around and smother the game. But Chelsea are just not allowing them to do it.
Chelsea are saying 'no', forcing the way they want to play on the game, keeping it at a high tempo.
Postpublished at 50 mins
Barcelona 0-1 Chelsea
The first shot on target this half - comes from Chelsea.
Ashley Lawrence cuts in from the left and fires an effort which is easy for Cata Coll to catch.
But still a sign of the visitors' threat.
Postpublished at 49 mins
Barcelona 0-1 Chelsea
No changes so far, both benches could prove crucial today.
Barca have a certain Alexia Putellas in reserve, but Chelsea's subs are very strong too. Millie Bright, Fran Kirby and Catarina Macario are among the options for Emma Hayes.
Image source, Getty ImagesPostpublished at 47 mins
Barcelona 0-1 Chelsea
Barca immediately come on the attack, Salma Paralluelo hanging in a high cross from the left which Chelsea have to deal with.
Aitana Bonmati then has a shot blocked, before the visitors are rescued by the offside flag.
KICK-OFFpublished at 13:33 British Summer Time 20 April
Barcelona 0-1 Chelsea
The players are back out in Barcelona.
Second half under way.
Elsewhere in women's footballpublished at 13:32 British Summer Time 20 April
HT: Bristol City 0-1 Liverpool
There's one game in the WSL today, which is kicking off at the same time as this semi-final in a quintessential piece of women's football scheduling.
Liverpool are leading Bristol City at the break. Bristol, rock bottom of the league, will be relegated this weekend if they lose and West Ham beat Manchester City tomorrow.
If you want to dual-screen, you can follow the action from Ashton Gate here.
Postpublished at 13:29 British Summer Time 20 April
HT: Barcelona 0-1 Chelsea
Chelsea have been so good so far, even Arsenal legends have to applaud.
Image source, Twitterget involved Get Involvedpublished at 13:27 British Summer Time 20 April
#bbcfootball, text 81111 (UK only - standard rates apply) or WhatsApp 03301231826
I say this to everyone when talking about Barcelona, that they don't face any real competition in their national league. Aitana Bonmati has said much the same thing. This might well be the first time this season they've been under any sort of pressure. Interesting to see how they respond.
Dylan
'Energy will be hard to maintain for Chelsea'published at 13:26 British Summer Time 20 April
HT: Barcelona 0-1 Chelsea
Pat Nevin
Former Chelsea and Scotland winger on BBC Radio 5 LiveWe know what it is like playing against sides like Barcelona. The discipline should be straightforward for Chelsea to keep, the energy much, much harder to maintain.
They will pass and pass and pass, and you will have to chase, chase and chase some more and you will get tired.
The full backs will have to keep working up and down, but Chelsea have players on the bench they can bring on. It is about making the right decisions at the right times in the second half.
Postpublished at 13:25 British Summer Time 20 April
HT: Barcelona 0-1 Chelsea
13 February 2019. Barcelona are stunned 3-2 at home by Sporting de Huelva in Liga F.
They have not lost a competitive match at home since.
Just in case we haven't banged in hard enough just how well Chelsea are doing here.
Cuthbert steps up for Chelseapublished at 13:23 British Summer Time 20 April
HT: Barcelona 0-1 Chelsea
Emma Sanders
BBC Sport at Estadi Olímpic Lluís Companys
Image source, Getty ImagesWow. This has been an unbelievable performance from Chelsea so far.
They rode the early pressure from Barca in a new-look back five and have since threatened a few times in behind.
Emma Hayes strolled down the tunnel at the referee's whistle, looking pleased, while a few of the Chelsea players congratulated Erin Cuthbert.
Barcelona's players sprinted off the pitch individually, clearly keen to get inside and discuss what's going wrong.
The noise has dipped too. I just heard a Barcelona fan describe her feeling in one word which I can't say on here...
Postpublished at 13:22 British Summer Time 20 April
Barcelona 0-1 Chelsea
In the WSL, Chelsea have won all 13 matches this season where they scored the opening goal.
Can they take that form into the biggest match of their season?
'Much better than expected from Chelsea, Barcelona disappointing'published at 13:20 British Summer Time 20 April
HT: Barcelona 0-1 Chelsea
Pat Nevin
Former Chelsea and Scotland winger on BBC Radio 5 Live
Image source, ReutersSo far, so good and so much better than I expected it to be from Chelsea.
Barcelona have been disappointing but only because they have been made to be because they have been closed down and out thought by Chelsea. The change of tactics have worked an absolute treat for Emma Hayes' side.
HALF-TIMEpublished at 13:18 British Summer Time 20 April
Barcelona 0-1 Chelsea
So far, so very good for Chelsea.
They are 45 minutes from a truly seismic win in the Champions League.
Some boos as Barcelona leave the field. For all their possession, the reigning champions have underwhelmed so far.
'Barcelona being outrun'published at 13:17 British Summer Time 20 April
Barcelona 0-1 Chelsea
Pat Nevin
Former Chelsea and Scotland winger on BBC Radio 5 LiveBarcelona are known for being a fabulous passing team but they are being outrun at the minute.
The likes of Aitana Bonmati have had little influence in the game because it is not to her style at the minute. She thrives when legs get tired and spaces open up for the passes.
Image source, Getty ImagesPostpublished at 45 mins
Barcelona 0-1 Chelsea
Barcelona have had two-thirds of the possession so far, but not a single shot on target. Chelsea have stifled them, and landed a powerful punch.
We will only have one minute of injury time.
Postpublished at 43 mins
Barcelona 0-1 Chelsea
How will the home side, the champions of Europe, respond?
They have not lost a competitive match at home since 2019. But they have serious work to do.
Postpublished at 13:12 British Summer Time 20 April
Barcelona 0-1 Chelsea
Emma Sanders
BBC Sport at Estadi Olímpic Lluís CompanysSTUNNED.
That's what the Barcelona fans are feeling inside Estadi Olímpic Lluís Companys.
Erin Cuthbert leapt into the air and ran over to the far side to celebrate while the Barca fans momentarily paused their chanting and drum banging.
A brilliant goal.