We take a look at five links between the two clubs ahead of Sunday’s semi-final showdown at Wembley...
Academy graduate Shaun Wright-Phillips made over 150 senior appearances for the Blues between 1999 and 2005, scooping City’s Young Player of the Year award an unprecedented four years in a row between 2000 and 2003.
Chelsea had seen enough and splashed the cash to sign him in 2005. The London-born winger struggled to hold down a starting place during his three years at Stamford Bridge, although he did start the 2007 FA Cup final when Chelsea triumphed over Manchester United.
Returning to City in 2008, SWP played another 64 times before the arrival of David Silva saw him slide down the pecking order, prompting a move to QPR.
Manchester-born Clive Wilson came through the City youth team, making an appearance as a finalist in the 1980 FA Youth Cup.
He made his first senior appearance for the Blues in the League Cup in 1981, and went onto play 119 times for the club.
Hugely popular with Blues fans due to his ability going forward from left back, he suffered relegation and promotion with City before moving to Stamford Bridge in 1987.
The defender was part of the side that romped to the Second Division championship in 1989 before switching to QPR.
Signed for a then club record fee by Kevin Keegan in 2002, Nicolas Anelka grabbed 37 league goals for City in 89 appearances and was top scorer in his second season at the club.
Anelka left in January 2005 for Galatasaray, but made a swift return to England 18 months later with Bolton Wanderers, before switching to Chelsea where he won the Premier League and two FA Cups.
A particularly impressive season saw the striker pick up the Premier League’s golden boot in 2009.
The Frenchman currently plies his trade for Juventus after a brief spell in China.
Currently on loan with Brighton in the Championship, Wayne Bridge swapped the blue of Chelsea for the sky blue of City in January 2009.
During his time at Stamford Bridge, he was part of the squad that won the Premier League in 2005, as well as collecting the FA Cup and League Cup double in 2007.
On signing for City, the left back became an immediate first-choice and went on to notch 42 league appearances for the club.
The arrival of Gael Clichy and Aleks Kolarov made for limited opportunities, and he has since spent time on loan at West Ham and Sunderland.
Former Welsh international Mark Hughes spent 18 months as City boss, arriving in the summer of 2008 from Blackburn.
Players such as Vincent Kompany, Pablo Zabaleta and Gareth Barry all signed during his time in charge, but after a run of seven straight draws he left the club in December 2009 to be replaced by Roberto Mancini.
His three-year association with Chelsea came in his playing days – arriving at Stamford Bridge in 1995 after his second spell with Manchester United.
The striker chalked up 123 appearances in a Chelsea shirt, as well as picking up FA Cup, League Cup and Uefa Cup Winners’ Cup medals.
City are back in Premier League action on Wednesday against Wigan - get your tickets here.