Emma Hayes revealed she felt “unwell” at the end of her time as Chelsea boss due to the stress of the job.

Hayes, who ended her 12-year reign in charge of the Blues to become head coach of the United States women’s team, is back in London as her new side prepare for Saturday’s friendly with England at Wembley.

The 48-year-old, who guided Chelsea to a fifth successive Women’s Super League title in May, opened up about the toll the job took on her health before she made the switch to international management.

Speaking in Camden about the perks of international football, Hayes told reporters on Monday: “I don’t have to sacrifice the things that made me healthy. I didn’t feel healthy at the end, I actually felt unwell at the end of my time at Chelsea.

“It wasn’t pressure, it was the stress and toll it took on me and doing that during menopause was even harder.

“To get on top of all of those things, I’ve got my mojo back and my smile and enjoyment back which I didn’t realise I had lost.”

Hayes guided the USA to Olympic gold in Paris in the summer and Saturday’s match will be the first time she has come up against Sarina Wiegman’s Lionesses.

Hayes admitted it would be strange going up against players she has “gone to war with” but said the occasion was strictly business.

“I’m looking forward to seeing Sarina,” she said. “Of course I need to go through a weird moment when the national anthems are being played. I’ll hum along to it (God Save the King) being the English person I am, but also the same for the US one because I love it, I love both anthems.

“Beyond that weird moment and coming up against players I’ve gone to war with, it’s business come kick-off. I hope it’s an entertaining game and a sell-out.”

Chelsea captain Millie Bright is one of a number of Blues players who will be up against their former coach.

“Millie Bright is a special person in my life and she feels like a little sister,” Hayes added.

“We went through many years of building Chelsea and winning titles and watching her at England, she’s someone that will be in my life beyond this football match.

“I’m looking forward to seeing her.”

England Women face Emma Hayes’ USA side at Wembley on Saturday November 30 (kick-off 5.20pm) and you can follow the game across Sky Sports’ digital platforms.