
It doesn't happen very often but players have crossed the divide in Manchester from red to blue and vice versa over the years.
Plenty have played for both clubs having represented others in-between, with the likes of Peter Schmeichel who won the treble and multiple Premier League titles with United during the Nineties representing City in the closing stages of his career.
Denis Law - the King of the Stretford End and part of United's Holy Trinity with Sir Bobby Charlton and George Best - famously played for City in two spells, the latter of which concluded with a backheeled goal against United as the Old Trafford club was relegated to the Second Division in 1974.
There have also been others where the move has been controversial, none more so than Carlos Tevez moving from United to City in acrimonious circumstances in 2009, while Owen Hargreaves made the same move in 2011.
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And Terry Cooke - who came through the youth team ranks at United at the same time as the Class of 92 including Paul Scholes, David Beckham, Nicky Butt, Gary Neville, Ryan Giggs and Phil Neville - made the switch to City in 1999 when the Blues were still playing at Maine Road.
But one of the most recent players to move directly between both clubs saw a defender switch from City to United back in 2012 and it came under Sir Alex Ferguson's tenure.

Frederic Veseli was on City's books as a youngster after joining from Lausanne-Sport in his native Switzerland in 2008.
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He had not made an appearance for City's first team and had a contract request refused at the Etihad Stadium.
It was then that coach Rene Meulensteen approached Veseli and Ferguson himself got involved in negotiations, which proved key as the defender moved to United at the end of the January transfer window in 2012 on a free transfer.
At the time, the player's now former agent Adam Bouskouchi said: "Freddie has talked to several clubs, here and abroad. But he wants to become a top player in England and when Sir Alex spoke to him, it really impressed him.
"He is a person who is hard to say no to and his record was enough for Freddie to think that the decision to join United was the right one."
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Ultimately, Veseli did not make an appearance for United's first team either and he was released at the conclusion of his contract in the summer of 2013.
Since then, the Albania international - who he qualifies to represent due to his parents being Albanians from Kosovo - has had a journeyman career with spells at clubs in England including Ipswich Town, Bury and Port Vale, as well as a stint in Italy at Empoli, Salernitana and Benevento.
Most recently, Veseli, now aged 32, has represented Fatih Karagumruk in Turkey, Egnatia in Albania, and is currently playing for Sudtirol in Italy.
Topics: Manchester City, Manchester United, Sir Alex Ferguson, Premier League