‘When did I recognise that she was any good in her business?” says Sid Hayes, the 80-year-old father of Chelsea’s manager, Emma Hayes. “I’m going to tell you a story about the London Olympics.”

As Hayes sat next to her dad at Wembley for the Olympic women’s football final, she was to all intents and purposes unemployed. “There was the ceremony on the pitch where the three teams [USA, Japan and third-placed Canada] collected their medals,” Sid recalls. “Emma said: ‘Dad, you see those 50 people out there? I’ve coached 40 of them.’ I thought: ‘Wow, but you’re sitting here unemployed?’ It was time to come back.” That month, August 2012, she took the job at Chelsea.

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The 44-year-old created history this month, leading Chelsea Women to a first Champions League final, but in 2010 she had been fired by Chicago Red Stars. “She was heartbroken, absolutely devastated,” says her sister Rebecca. “It was a bit harsh – I think she was only five games in. That was the biggest learning curve of her life. That’s when she stepped back from football.”

After a stint as a consultant for a Washington Freedom team that included US internationals such as Abby Wambach, Hayes returned to London and worked for the family business, Covent Garden FX, a currency exchange.

“She needed something mundane, to come away from it, see if [coaching] is really what she wanted to do,” Rebecca says. “People were phoning her, wanting her to be involved in different clubs, but she needed that time out to assess, review and just enjoy growing something for the family. She built software systems, she built websites, she took it to another level. She put money online, which my dad could never understand.” For anyone who has followed Hayes’s Chelsea build, the pattern is familiar.

Hayes kept her toe in the football waters, working from London as technical director for Western New York Flash, whom she advised on transfers, helping to create a team that won the 2011 Women’s Professional Soccer championship. But the journey from where she was then to where she is now, preparing to face Barcelona in the Champions League final in Gothenburg, is remarkable – and to understand it fully it helps to go back to the beginning.

On the Curnock Street estate in Camden, north London, Hayes’s childhood was filled with football. An admirer of Diego Maradona, Paul Gascoigne and Gary Lineker – “Gary Lineker’s legs, she used to love those! In his little shorts!” her older sister Victoria says with a laugh – she played with the boys and was referred by a teacher at primary school, where she was the only girl to play, to a club called Mary Ward. “We used to beat everyone and Emma was always the star of the show,” says Rebecca. “She was a creative, tricky player, the goalscorer.”

It was, according to Victoria, a formative experience: “I think that’s where she got her winning mentality from. She had a team that played for one another. She learned the true spirit of teams working together.”

Hayes joined Arsenal’s academy but injured an ankle on a ski trip aged 17 and was told she would never play again. “She was just inconsolable,” Victoria says. “She was told she’s not supposed to kick a ball. That injury changed her.”

With football ruled out, Hayes did European studies, Spanish and sociology at Liverpool Hope. Her intention was to become a spy, and a master’s in intelligence and international affairs followed. “She can tell if you’re lying,” says Sid. “She learned all these tricks. When they started teaching how to assassinate people and that, it was time to leave.”

During university holidays Hayes assisted in various businesses in which her dad was involved, and displayed the work ethic that is part of her success. “She would get up at five o’clock in the morning, go there on her own and cook 2,000 baguettes,” says Sid.

In Liverpool, she had also started to pick up coaching badges, not only in football but in everything from swimming to table tennis. She worked in sports development for Camden council but there was an itch that needed scratching.

“I remember her lying in the bath; that’s how close we are, one would be on the toilet and one in the bath,” says Rebecca with a laugh. “She was like: ‘This is my time to change. I need to go where the elite is in this sport, where it’s the most professional, where I’m going to learn, where I’m going to grow and it’s going to be America.’ And as much as that was devastating for me, she was so determined. She just hated the culture, the hurdles, the politics in this country.”

Victoria and Rebecca drove her to the airport, the trio stopping en route for a good cry. Hayes had a one-way ticket, $1,000, a backpack of clothes and a job at MLS camps on Long Island. She did not need long to make her mark.

In 2001 Hayes became the youngest head coach in W-League history, with the Long Island Lady Riders; the following year she was named national coach of the year aged 25; and in 2004 she won a different coach-of-the year award with Iona College in New York, despite meagre resources. Eleri Earnshaw was her captain there. “We weren’t Chelsea, we weren’t the best team, but she demanded the highest standards,” the former Wales international says. “Because of that, we went into every game, rightly or wrongly, thinking that we could win, because of how hard we worked and how tenacious we were.”

Emma gave pink roses and a poem to her team on the bus to the 2015 FA Cup final and these days has her team watching motivational videos. In Earnshaw’s first year Mark Twain’s “It’s not the size of the dog in the fight, it’s the size of the fight in the dog” was on the back of training shirts.

Anson Dorrance, head coach at the University of North Carolina and mastermind of the USA women’s first World Cup win in 1991, met Hayes at a United Soccer Coaches course in Brazil and was “impressed immediately” by her football knowledge. “Here I am teaching the course and this little snot had better references for the game at the highest level than I did, so I obviously immediately took to her.”

But it was more than knowledge that caught his attention. “She is openly ambitious,” he says. “The trouble with the way we raise our girls and young women is we teach them to basically genuflect. She was confident back then but now she’s commanding. We praise men for having this quality [ambition] and yet we seem to excoriate women for it.”

For Dorrance, Hayes’s biggest takeaway from the US was not tactics or methodology. “I think she benefited from basically the status as an American coach in women’s football because in our country the women’s game is respected … The teeth of the patriarchy in sport in our country aren’t as sharp.”

Learning more about recruitment in the US was also key for Hayes, according to Amanda Vandervort, who was then head coach of NYU and would allow the Iona College coach to crash in her room on recruiting trips to save money. “In the college recruiting system you’re dealing with intense competition,” Vandervort says. “You have to try to convince players to come to your school when you have no budget, no scholarship.”

Katie Chapman, who played under Hayes at Arsenal, in Chicago and at Chelsea, says her former manager puts emphasis on personality as well as talent, searching for “a good person who you can trust and is going to fight for you”.

Hayes returned to England in 2006 – but not for long. After a successful spell at Arsenal Ladies as academy director and assistant to the legendary first‑team manager Vic Akers, including for the 2007 quadruple, the launch of a new professional league lured her back to the US. Chicago Red Stars and Saint Louis Athletica wanted her and before she travelled she visited a psychic – for the first and only time.

Hayes was told by the psychic that her choice did not matter, because she would have her main success at Chelsea. “We had a proper belly laugh,” says Vandervort. Chelsea were amateur then, not even on the radar.

Having plumped for Chicago, Hayes demonstrated her talent for recruitment. She signed Karen Carney and selected as her second overall pick in the 2009 draft a young Portland College forward: a certain Megan Rapinoe. The following year’s additions included Chapman.

Then she was fired. “We never look at failure as failing,” says Victoria. “Failure is the first attempt at learning, and that was her first attempt at learning to build a team. Second attempt at Chelsea of building a team was remarkably different.”

Chapman says Hayes has “built everything at Chelsea – from having the kit washed to having food, to having our own building, to having our own training and pitches. Now, it’s an absolute professional setup but everything’s been a fight over the years to do that. She’s always looking at how she can help everybody else.”

She “plays that role in the family”, says Rebecca, but family has also been crucial to her success, a support network through good and bad. She leaned on it heavily when she lost Albie, one of the twins she was carrying, at 28 weeks pregnant in 2018. Her family were desperate for her to take a step back, “but there was no stopping her”, says Rebecca.

“The last game of the season, she literally had to get pinned down: ‘You can’t go, you’re due any day.’ My mum very much supported her in all of it. She travelled to Wolfsburg, went on 10 million trains with her, and then we had to get our cousin who was a midwife to take her on another journey when it got really close. The doctors were advising her not to do it, but she did it. Nothing would stop her, not even her own health. It’s all about the team – she’d do anything for winning.”

Becoming a mum to Harry, though, is what Hayes counts as her biggest achievement. Again, her family are there to help. They will head to her house in shifts while she is away for this final, looking after Harry in his own environment. “He watches her on the telly but he just wants to get in the telly,” says Rebecca. “You ask Harry: ‘What is Mummy?’, and he says, ‘A winner!’”

To watch her move one trophy closer to matching Arsenal historic quadruple would be a proud moment for her mentor Akers, who messages her before every game. “If I ever wanted anybody to take that sort of accolade, winning the Champions League, it would be her,” he says.

Rebecca cried for an hour after Chelsea reached the final. “And my father did too – you would never see a weakness in him or any sort of emotion but he did exactly the same.” Victoria says she spent the last minutes of the semi-final on the floor with a pillow over her head and her watch warning her heart rate was too high.

What keeps Hayes wanting more? Sid, says Chapman. “He’s her hardest critic. He doesn’t let her get away with anything. That’s what drives her.”

Rebecca says: “He always wants more. You’re never ever rewarded with a ‘well done’. It’s just: ‘You’ve done that, what’s next?’”

He does say he is proud though, unprompted, when he remembers seeing Hayes’s impact at a United Soccer Coaches convention in the US. “This little girl from Camden teaching all these international coaches at the biggest coaches convention in the world: wow,” he says. “She has a presence, Emma, at these places. I’m well proud of her obviously. She’s got a skill, a skill you can’t buy.”