Manchester City manager Nick Cushing is to leave the Women's Super League club after more than six years in charge.
The 35-year-old is to take up the assistant manager's position at men's team New York City of the MLS in the United States.
His final match as Manchester City boss will be at home against WSL champions Arsenal on 2 February.
Since taking charge in 2013, Cushing has won six major trophies, including the 2016 WSL title and two FA Cups.
Cushing, who said the decision to join Ronny Deila's New York City was not "taken lightly", has been the club's only manager so far in the WSL era since they joined the top flight in 2014.
"We've had an amazing six and a half seasons and I have thoroughly enjoyed working with everybody - I will be extremely emotional to leave," he told Manchester City's website.
"Linking up with New York City and Ronny (Deila) is a brilliant opportunity and I'm really looking forward to working in the MLS."
'He will be missed, but everybody is thrilled for him'
In his time as City boss, he has overseen their rise to become a dominant force in the English game.
In each of the past four seasons they have qualified for the Women's Champions League but, after reaching the semi-finals in their first two European campaigns, they have failed to progress beyond the last eight of the competition.
After leading City to their maiden league title he was shortlisted for the England women's job, but withdrew from the process before Phil Neville was handed the role.
He will leave City with 18 months left on his contract, having signed a three-and-a-half-year deal in December 2017.
City are second in the WSL table after 11 games, just three points adrift of leaders Arsenal.
His planned departure after the Gunners visit the Academy Stadium in February means he will remain in charge for five more games, which includes a Women's FA Cup fourth-round tie against local rivals Manchester United.
Cushing's assistant, former Tranmere and Republic of Ireland midfielder Alan Mahon, is set to take over as interim City boss.
The move for Cushing, while into the men's game and across the Atlantic, sees him remain employed by the City Football Group, which owns Manchester City, the New York club and a number of other sides globally.
"He will be missed, but everybody here is thrilled for him and this exciting new venture within the City Football Group," said Gavin Makel, Manchester City's head of women's football.
Tom Garry, BBC Sport
Cushing has been one of the most successful managers in the modern era of women's football, lifting the FA Cup at Wembley twice in the past three years and leading City to four of the past five League Cup finals.
His team have not finished outside of the top two spots in the WSL since 2014 and, along with Arsenal and Chelsea, have dominated domestically for five successive campaigns.
But as well as getting used to winning silverware, Cushing has also developed a strong reputation for nurturing young home-grown talent.
He named an entirely British starting XI - nine of whom were English - for a 2-0 win over Chelsea in September 2016 that clinched the club's first WSL title.
He may forever be disappointed not to have reached a Champions League final - having lost narrowly on aggregate to Lyon in the last four in 2016-17 and 2017-18 before back-to-back eliminations at the hands of Spanish giants Atletico Madrid in the past two campaigns.
Nevertheless, one of his key lasting legacies is set to be the wealth of English talent the club can now boast, which was rarely better emphasised than at last season's FA Cup final at Wembley, when all three of Manchester City's scorers in a 3-0 win over West Ham United - Keira Walsh, Georgia Stanway and Lauren Hemp - were English and under the age of 22.
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