Liverpool and Manchester United have a footballing rivalry steeped in history, bad blood, and unforgettable feats on the pitch.
As you might expect in a spat of this magnitude, not many players have turned out for both sides.
Here are those who have:
Double Agents: Players to have played for both Liverpool and Manchester Utd
Chisnall was a forward that played throughout the 60s and 70s and is currently the most recent player to be directly transferred between the two clubs.
Born in Manchester, he started his career with the Red Devils making 47 appearances and scoring 10 goals before signing for Liverpool in 1964 for a fee of £25,000.
He only managed two goals in eight appearances in two years on Merseyside before moving to Southend and then Stockport County for the remainder of his career.
A defender who played in the early 19th century, Chorlton played for Stockport County and then Accrington Stanley before signing for Liverpool in 1904.
He went on to make 117 appearances for the Reds and scored eight goals before moving to United in 1912.
He only managed four appearances for the Red Devils in two years and left for Stalybridge Celtic in 1914 were he finishes his career.
Beardsley was born in Hexham in the North East and began his career with Carlisle United and moved to Vancouver Whitecaps in Canada in 1982.
After impressing abroad, scoring 20 in 48 games, the attacking midfielder moved back to England with Manchester United in the same year.
However, he failed to get going and only managed one appearance in the League Cup, moving back to Vancouver and then to boyhood club Newcastle United in 1983.
He picked up great form for Newcastle and earned himself a move to Liverpool in 1987 – he made 131 league appearances and scored 46 goals for the Reds. Also winning the First Division twice and an FA Cup.
He then went on to turn out for a plethora of different clubs throughout England – finishing his career in 1999 with Melbourne Knights in Australia.
Ince started his career with West Ham and moved to United in 1989 making 206 league appearances for the Red Devils and scored 25 goals. He won the Premier League twice, the FA cup twice and won a League Cup with United.
He then moved to Italy with Inter Milan in 1995 playing there for two years before moving to Liverpool in 1997.
Despite winning no honours Ince performed well for Liverpool over his two-year spell leaving to join Middlesbrough in 1999.
Three years in Teesside ended with a four-year spell with Wolverhampton and then after three appearance for Swindon in 2007 – Ince ended his career with one game for Macclesfield in 2007.
A pacey forward with a fantastic finish, Owen started his career with Liverpool, making his debut in 1996.
He went on to make 216 league appearances for the Reds and scores 118 goals – also winning the FA Cup and League Cup and UEFA Cup in 2000/01 and the League Cup again in 2002/03. He also won the Ballon D’Or in 2001.
After becoming a club legend Owen moved to Real Madrid in 2004 but could not find the form he had for Liverpool, moving to Newcastle two years later.
After letting his contract run out in Newcastle Owen signed for United in 2009, much to the disappointment of Liverpool fans.
He went on to make 31 appearances for the Red Devils, scoring five goals and winning the Premier League and the Football League Cup over the course of three years.
Stoke City was where he finished his career, only managing eight appearances and one goal in the 2012/13 season.
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