They say the grass isn't always greener... and that is often true when a footballer leaves a club of Manchester United's stature.
United fans have witnessed many comings and goings in recent years - most notably following Erik ten Hag's arrival as manager last summer. The former Ajax boss brought in the likes of Christian Eriksen, Casemiro and Lisandro Martinez after his appointment.
Ten Hag also let a number of players go. Although it was time for many of these stars to move on, some of the transfers have not worked out. Here, Mirror Football takes a look at seven recent United players who have struggled since their Old Trafford exit.
Paul Pogba
Perhaps the obvious name on the list. Pogba, 30, left United when his six-year deal expired last summer and re-joined Juventus. The France international has struggled since that transfer, as he has played just twice in Serie A due to knee and muscle injuries.
Pogba was forced to sit out the World Cup in Qatar and it is unclear where his future lies, with rumours suggesting Juventus are unhappy with the midfielder's fitness. As such, Pogba may regret not putting pen to paper on an extension at Old Trafford midway through his now-expired deal. He certainly has ability to prosper under a manager like Ten Hag.
Edinson Cavani
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Like Pogba, Cavani left Old Trafford as a free agent last summer. Although it was time for the 36-year-old to move on, his stint at Valencia is not going to plan. Injuries have restricted the forward to just 18 club appearances in all competitions this season.
Cavani's record in Spain is good - scoring seven goals - but Valencia are enjoying a woeful campaign. The Spanish giants are one point from safety in LaLiga and could suffer a surprise relegation this season. It might be time for Valencia to bring back Gary Neville...
Jesse Lingard
Lingard played just 16 Premier League games for United during his last two seasons at Old Trafford and moved on when his contract expired last summer. The Englishman signed for Nottingham Forest shortly after his exit... but the transfer has not gone to plan.
Lingard has not scored a single Premier League goal for Forest, who are in the middle of a relegation battle. The 30-year-old is set to become a free agent again this summer, and he will struggle to find another Premier League club if his form does not improve soon.
James Garner
Garner was an upcoming star at United when he decided to join Everton in a permanent deal last summer. The 22-year-old's transfer followed a superb 2021/22 campaign at the City Ground, where he helped Forest win promotion to the Premier League.
Yet injury has restricted Garner to just seven outings this season - the most recent of which came in November. He has since returned to fitness and made the bench for the last three games, but perhaps he should have rejected Everton's advances last summer.
Garner told The Times in November, "In the moment it is very disappointing. That was the club that I trained with five times a week for years and years and years, that I made my debut with. But I didn't want to stagnate."
Garner went on to say, "I know in myself I wouldn't have played if I had stayed. I knew it was the perfect time now, at 21, to move on and try and stake my claim somewhere else and hopefully find a home, which I have now in Everton."
Daniel James
James was deemed surplus to requirements when Cristiano Ronaldo returned to United in August 2021. The Wales international acted quickly by joining Leeds in a £25million deal - deciding against staying at Old Trafford and fighting for his place.
James, 25, played regularly for Leeds last season but made a surprise loan move to Fulham in September. He has played just 14 minutes of football during Fulham's last seven league games and it is unclear where his future lies. Another loan move is a possibly.
Ander Herrera
United's midfield struggled after Herrera joined French giants Paris Saint-Germain on a free transfer in the summer of 2019, as the likes of Fred and Scott McTominay failed to fill the void. Casemiro and Eriksen have since resolved that issue, of course.
Yet the transfer did not work out for Herrera, either. The Spain international, 33, played only 58 league games during his three-year spell at PSG and is now back at Athletic Bilbao - the club he left to join Louis van Gaal's United in the summer of 2015.
Herrera was asked what his biggest United regret was on leaving the club. The dynamic midfielder said, "That [winning the Premier League] was one of my dreams. I have won some trophies, but the league is something I wanted to win."
Ashley Fletcher
Many United fans will not remember Fletcher, who turned down the offer of a new contract at Old Trafford in the summer of 2016. He then joined West Ham and has since become an established Championship striker - currently playing for basement club Wigan.
The 27-year-old joined the Latics on loan from Watford earlier this season after spells with Middlesbrough, Sunderland and New York Red Bulls. Despite his career not quite going to plan, there is still time for Fletcher to climb his way back to the Premier League.
"At the time the manager was Louis van Gaal - a real character and a great guy, to be fair," Fletcher told the Judy podcast. "But if you weren't playing in the first team you had to play in the U23s that week, so that was killing me, [Marcus] Rashford and Will Keane."
Fletcher admitted that he was not even guaranteed of a place in the U23s - let alone the first team - due to senior strikers dropping down to gain fitness. "It was like waiting for a chance to play in the U23s and I'm like, I could be 21 by the time I play," he added.
