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
Supporters of FC Barcelona development of a larger national fan-base has created friction between the Catalan nationalist supporters, who wish to secede from Spain, and the club's other Spanish supporters. There exist four different types of supporters of Barcelona; one is the "soci" or club-member, who is eligible to vote in the presidential election of the club and other matters. The "penyes", who are closely affiliated with the "socis", are fan-clubs, which in the past have been responsible for large donations to the club. Also, there are "Barça Fans" and this term refers to the official online fan community of the club where these