West London derby been in the Football League for a longer period of time than Brentford and had stronger rivalries with the likes of West Ham United and Tottenham Hotspur, whereas Brentford's main rivals are Fulham and QPR. Also Brentford developed a bigger sporting rivalry with Arsenal at the time as both clubs vied for the title of London's number one club. The only bad feeling between the clubs was soon after Chelsea's foundation and admission into the Football League in 1905, the other West London clubs, including Brentford, lost many supporters and potential supporters to the only professional Football League club in
Football in London they were the first London team to win the Football League First Division in the 1930–31 season and the first London club to win the Premier League in the 1997–98 season. Chelsea are the only London club to win the UEFA Champions League, which they did at the 2012 tournament. On 15 May 2013, Chelsea won the UEFA Europa League to become one of five clubs to win all three main UEFA club competitions. Chelsea are also the only London club to participate in the FIFA Club World Cup. They were runners-up in 2012, losing to Corinthians of Brazil in