Resilient, street-smart and clinical when it mattered, Chelsea launched the most audacious smash and grab on the European champions to take a one-goal advantage back to Stamford Bridge as they bid to reach the Champions League final in Emma Hayes’s final season in charge.

It was the captain, Erin Cuthbert, who fired them ahead at the end of the first half, a player who less than 24 hours before had said these games bring out the best in her.

Related: Barcelona 0-1 Chelsea: Women’s Champions League semi-final, first leg – live reaction

It was a defensively resolute and intelligent performance. The Blues limited the home team, who had not failed to score in a game since April 2022, to one shot on target – which came in the eighth of nine minutes of injury time.

The victory was all the more remarkable given that Barcelona had not lost since May, not lost in the Champions League since a 3-1 group stage loss to Bayern Munich in December 2022 and not lost at home since February 2019.

“I’m not here to break records, no disrespect to Barcelona, but that’s not a trophy for me,” said Hayes. “We’re here to compete for the Champions League and we’re at half-time against the best team in the world, who didn’t have their best game today.”

Lyon pulled off a stunning late comeback to snatch a 3-2 win at home to Paris Saint-Germain in their all-French Women's Champions League semi-final first leg on Saturday, with all three Lyon goals coming in the last 10 minutes.
Lyon, whose eight Champions League titles makes them the most successful club in the competition's history, started well and exerted plenty of pressure, but PSG soaked it up comfortably before hitting them with a pair of sucker punches.
PSG striker Marie-Antoinette Katoto broke the deadlock in the 44th minute as Lyon defender Ellie Carpenter stood off her, leaving her just enough space to rifle a low drive into the net despite losing her balance in the process.
Three minutes into the second half Katoto struck again. Played onside by Selma Bacha, Katoto latched on to a blocked shot and pulled the trigger quickly to double her side's lead.
That goal provoked a strong response from Lyon but it took until the 80th minute for them to pull a goal back, Kadidiatou Diani toe-poking the ball into the bottom-left corner to set up a frenetic finish.
Five minutes later Lyon were level as Melchie Dumornay curled a sensational effort into the top corner, and a minute later substitute Amel Majri grabbed the winner with a superb turn and shot. Reuters

Hayes set Chelsea up unconventionally for a team so used to dominating, with Ashley Lawrence and Johanna Rytting Kaneryd the wing-backs either side of Jess Carter, Kadeisha Buchanan and Niamh Charles in a back five.

Chelsea know what it takes to deny the fluid and mercurial Barcelona in their own stadium. Last season they earned a 1-1 draw at Camp Nou, but the damage had been done in the 2-1 home defeat and the Blaugrana went on to win the final.

This is a slightly different Barcelona though, one that conceded four goals against Benfica in a 4-4 draw in the group stage and also conceded twice against Brann over two legs in the quarter-finals.

At the Estadi Olímpic, this was a savvier Chelsea and the three centre-backs were superb in limiting chances. By the break, Barça had launched five attempts on goal but none on target. Chelsea had one effort on target and were one goal up.

“You know everything has to be perfect for you to get close to winning a game of football [against them],” said Hayes. “We took our chance. Our team did a lot to limit chances as a whole. You can only do that together and not individually.”

The first half played out like the most intense of chess matches, but it was the drive of Sjoeke Nüsken and the hunger of Cuthbert that stunned the home crowd five minutes before the break.

A Charles throw-in was met by Irene Paredes but under pressure from Mayra Ramírez her pass was intercepted by Lawrence. The wing-back pulled it back to Cuthbert whose first-time pass found Nüsken in space. She controlled it, turned and returned to Cuthbert, who took two steps to move away from Ingrid Engen before lashing in with ferocity.

The 36,428 fans in attendance were stunned, the small pocket of Blues tucked high into the upper tier watching through a clear plastic shield barely audible in their celebrations.

Six minutes after the restart Patri Guijarro’s effort came back off the outstretched arm of Buchanan. The referee, Stéphanie Frappart, pointed to the spot before a lengthy wait for a VAR check concluded with Salma Paralluelo adjudged to have been offside as the ball struck Buchanan’s arm.

Chelsea were clever with their game management, frustrating the home team. They continued to soak up the pressure and look dangerous on the break. They went close to extending their lead when Ramírez was released through the middle, half shrugging free of Guijarro before firing over.

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They were clinging on at the end as Barça pushed for the goal that would reset the tie, but defended collectively to hold on to their lead. Barcelona’s Alexia Putellas fired wide from close range with the final kick of the game.

There were only muted celebrations though, the job half done. The desire now is to take advantage of being at home, a sell-out at Stamford Bridge the goal.

“It’s essential, we’ve watched many clubs sell stadiums in the biggest games,” said Hayes. “Our girls deserve it. They deserve to play in front of a full house to give ourselves the best possible chance because we are going to need them. Barcelona will throw absolutely everything at us.”