Having departed Chelsea in May after a sensational 12-year period that saw her win 14 major trophies and five successive Women's Super League titles, she decided it was time to pursue a new opportunity outside club football.
That led Hayes to the USWNT, and she arrived with only two months to prepare for the Paris Olympics.
With just four warm-up games to get her new team into shape for the competition, few were talking about the USA as serious contenders for the gold medal.
But as she has done so much in her spectacular coaching career, Hayes found a way to win.
She led the US to a 1-0 victory over Brazil at the Parc des Princes in Paris, and the result saw the nation secure their first women's football gold since 2012.
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The Olympic triumph came just 84 days after Hayes won the WSL title with Chelsea, and suggested that there will be plenty more to come as she settles into her new role.
Next up for the USWNT is a friendly against England at Wembley Stadium.
And as she returns to London, Hayes has been reflecting on her first few months with the US team, and how she led them to Olympic gold with next to no preparation.
"When I went in, it was like an emergency surgery," Hayes told talkSPORT.
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"I had to say to everyone in it, 'Whatever your job was, for now we need you to do what we need to do to get us through the Olympics. I need to lead it a certain way. Then after the Olympics, we can shape it together'.
"Everybody had to put their ego to one side so we could get the team to perform a certain way, with four or five games, and maybe 10 (training) sessions of preparation. That's not a lot.
"We had to get it right in the classroom, and get it right on the grass. But they were hungry to win, and their performances at the World Cup set me up really well."
Hayes went on to praise her staff and players for pulling together to achieve Olympics success after a tough World Cup in 2023 that saw the US eliminated in the round of 16.
"They were so humble, so quick to learn and adapt. Most importantly, they were great team players, they wanted to take on any ideas I gave them and they delivered it," she concluded.
At the Olympics, the USWNT won every match en-route to gold.
Quite incredibly, they never trailed a game, beating Zambia, Germany and Australia in their group, before wins against Japan in the quarterfinals and Germany again in the semis.
In the gold medal match, Mallory Swanson's goal secured a 1-0 victory against Brazil as the new era began with success.
The USWNT face European Champions England next, offering Hayes another chance to impress on the big stage with her new team.