Chelsea boss Emma Hayes insisted opponents Manchester City sold her side short after Sam Kerr's extra-time winner handed the Blues their fourth Vitality Women’s FA Cup.

In front of a Women's FA Cup record 49,094 fans, City dominated the opening exchanges at Wembley but Hayes’ side struck first after Kerr glanced in Millie Bright’s cross on 33 minutes.

Lauren Hemp levelled before the break and Chelsea pulled ahead through Erin Cuthbert before substitute Hayley Raso’s last-gasp effort ensured the sides went to extra time, when Kerr struck for 3-2 victory. Hayes, however, was never in doubt.

“I know when I lie in bed later I’ll be thinking about the moment standing in the huddle at extra time,” she said.

“I stepped out of it and I could see Magda communicating and Jonna communicating about what we needed to do there. It was completely calm. It was leadership at a level that I’ve worked so hard to try to cultivate in the environment.

“It’s not just about one person, me, making decisions and what it takes to win. It’s not always pretty. I think Man City are a top team but I think they underestimated us today. We had a point to prove and I thought we did really well with that.”

It was City who enjoyed more early chances as Chloe Kelly’s shot from the right was easily picked out of the air by Ann-Katrin Berger, the first time either keeper was tested.

But the Blues showed their strength at the back as City continued to test the Blues, who regained possession and played Kerr in on goal as she fired past City keeper Ellie Roebuck before being called offside.

It still appeared to fire up the Barclays FA WSL champions, Millie Bright in full control as she received a pass from Jess Carter at the corner of the box, whipping a cross to the far post for Kerr to glance it over the head of a leaping Roebuck to break the deadlock on 33 minutes.

It wasn’t long, however, before Hemp, who had caused problems for Chelsea throughout the first half, swirled around her marker and there was nothing Berger could do about her curled effort into the right corner to ensure the sides were level at the break.

Roebuck was called into action again, easily catching Guro Reiten’s cross as play resumed, but the Blues pulled ahead through Erin Cuthbert, whose powerful strike caught the underside of the crossbar and bounced in.

Both sides made late substitutions but it was Gareth Taylor’s that paid off, Raso’s fresh legs off the bench giving her the boost of speed she needed to beat Chelsea skipper Magda Eriksson to the ball and lob the leveller past Berger.

Nine minutes into added time Kerr picked up the ball in midfield and powered down the pitch, sending a low strike into the right corner that was heavily deflected off the unfortunate Alanna Kennedy to seal the double for Barclays FA WSL champions Chelsea.

And Hayes, who swatted away rumours of an impending departure with a firm “I don’t have to kill any speculation, I’m under contract at Chelsea and there’s nothing to talk about,” preferred to discuss her players’ collective legacy.

She added: "They will go down in history. I will look back in ten years’ time and think ‘that group was immense.’

"It’s the best team I’ve coached. We always want to talk about perfection in football but having been on the winning side more often than not, it’s about human endeavour. We have a group of people that don’t want to be on the losing team. They find a way.”

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