While it may be judged in bad taste to play for both Chelsea and Arsenal, or Liverpool and Manchester United, turning out for both the west London club and the team from Anfield has yet to reach such a controversial nature.
Many of the biggest names in the Premier League have played for both, indeed many have signed directly from one to the other, and so ahead of the big game this weekend, we’re running the rule over five of the biggest successes – or flops, to have played at Chelsea and Liverpool.
Where else could we start this little quintet than with the £50m pound man…
Oh Fernando. Nothing short of incredible for three seasons at Liverpool, a failure to overcome injuries saw him return from the 2010 World Cup a shadow of his former self.
Nevertheless, Roman Abramovic saw fit to shell out £50m in January 2011 to take Torres to London.
In three and a half years Torres never scored more than eight in the league, and while there were highs – that goal against Barcelona at the Nou Camp – it was largely a disaster at Stamford Bridge with poor Torres tripping, stumbling and missing open goals at Old Trafford.
Enough was enough and Torres departed for AC Milan in the summer of 2014 on a loan-deal which soon became permanent, ending a real rollercoaster journey in England.
Joe Cole’s story is scarily identical to Torres’, just in reverse.
Signed by Claudio Ranieri from West Ham in 2003, Cole became a rare outlet of reliability in the early part of the Abramovic era and Cole eventually won eight trophies in a seven-year spell.
Success was not replicated when he joined Liverpool as Roy Hodgson’s first signing in 2010.
Sent off on his league debut against Arsenal, Cole then missed a penalty in his next appearance for the Reds and things never recovered, eventually leaving just two years later for a return to West Ham.
Chelsea and Liverpool made up just two of Nicolas Anelka’s six Premier League clubs.
An impressive loan spell at Anfield in 2001-02 had many expecting then-Liverpool boss Gerard Houllier to sign ‘Le Sulk’ permanently.
Houllier decided to sign El Hadji Diouf instead (we don’t know why either) and after spells at Manchester City and Fenerbahce before an impressive goal return at Bolton, Anelka joined Chelsea in 2008.
A fine 19 league goals in the 2008-09 campaign was his highlight in four years at the Bridge, but a return of one Premier League, two FA Cups and a Community Shield isn’t bad for a man who was nearly 30 when putting pen to paper.
How both Chelsea and Liverpool could do with a fully-fit Daniel Sturridge now.
After failing to make the cut at Man City, Chelsea thought Sturridge was the man for the future. 11 goals in 30 appearances during the 2011-12 season suggested the Englishman was at the Bridge for good.
But it was not to be and Sturridge joined Liverpool in January 2013. 31 league goals in his first 43 games made him a fan favourite on the Kop and he was an integral part of the team which came so close to the Premier League title in 2014.
Injuries have sadly blighted both him and Liverpool ever since.
Another who made the move from Upton Park to west London in 2003, Johnson made 35 league appearances in his first two seasons at Stamford Bridge before being outcast in a wave of Abramovic signings.
A spell at Portsmouth kick-started his career and Liverpool won the battle for his signature in 2009.
Johnson spent six seasons up and down the right flank, quickly making the right-back spot his own in the red half of Merseyside.
After 200 appearances, nine goals and an equal measure of dazzling and bemusing performances, Johnson departed Anfield this summer to join Stoke City.
And it hasn’t just been players who have tried their hand at these two Premier League heavyweights…
Rafael Benitez spent six years at Anfield but could wrestle the Premier League away from Sir Alex Ferguson, leading to his public outburst of ‘fact-gate’.
But while the Premier League eluded the Spaniard, he will always be revered in Liverpool hearts for the incredible Champions League success in 2005.
The current Real Madrid boss is held in slightly lower regard by Chelsea fans, despite European success with the Blues too.
Replacing Roberto Di Matteo in November 2012, Benitez could do little to repair early season damage in the league and in Europe.
Special mentions should also be given to Bolo Zenden, Yossi Benayoun and Raul Meireles who provided plenty of entertainment for both teams down the years.
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