They may be one of the most successful club's in England and standout among Europe's elite, but Chelsea do not have a clear traditional neighbour with whom they share a serious rivalry.
Blues fans tend to give a variety of teams whom they consider to be their fiercest enemies, but opinions will tend to differ from supporter to supporter, often depending on their generation.
However, five clubs stand head and shoulders above the rest in terms of the resentment felt towards them by the Stamford Bridge faithful in the main...
5. Leeds United
A rivalry that was born during highly physical encounters between the sides in the 1960s and boiled over in the ill-disciplined 1970 FA Cup final; Chelsea vs Leeds is a game which has the authorities on red alert.
The clubs gained notoriety for their hooligan firms and, in Chelsea's 5-0 victory over Leeds in 1984, the latter's supporters tore apart the Stamford Bridge scoreboard.
The animosity between the clubs has quietened in recent years - due to Chelsea's rise, and the plight of the Elland Road club, fixtures between them are now few and far between.
4. Manchester United
The only club who have won more Premier League titles than the Blues - the Red Devils are hated above all others by many younger Chelsea fans. Even Roman Abramovich's spending spree was not able to halt United's success under Sir Alex Ferguson.
In Chelsea's first Champions League final, in 2008, United beat them on penalties; despite the Blues having been within one kick of winning the competition.
The north London side have traditionally been the capital's most successful club and, with 13 league titles, they boast a tremendous history.
Chelsea's recent glory has heightened tension between the clubs. The Blues were fined for allegedly illegally approaching then Arsenal left-back Ashley Cole in 2005. Cole went on to feature in Chelsea's Champions League success in 2012 - which poured salt into the Gunners' wounds, as they have yet to win the trophy.
Animosity between some older fans of the clubs stemmed from allegations made about Chelsea supporters regarding the Heysel disaster and their then chairman, John Smith, claiming that the culprits were probably from London.
However, Chelsea's recent success - and Luis Garcia's controversial "ghost goal" in the 2005 Champions League semi-final - has taken the rivalry between the clubs to a new level.
Chelsea's controversial £50 million signing of Fernando Torres from the Reds further heightened the mutual hatred between the sets of fans.
1. Tottenham Hotspur
The close proximity between the clubs created a rivalry that intensified after the 1967 FA Cup final, when a Tottenham side containing former Chelsea stars Terry Venables and Jimmy Greaves beat the Blues.
In recent years, the roles have been reversed. Spurs slipped behind Chelsea in the league during the 1990s. The latter's Champions League triumph in 2012 meant that the former did not feature in the following season's competition, despite having finished fourth in the league.
The latest point of conflict between the clubs was when Willian signed for Chelsea in 2013, despite having completed a medical at Tottenham. The jealousy that has always fuelled this rivalry has now swung the other way.