During their history, the club have been known by a number of nicknames including Los Colchoneros or The Mattress Makers due to their first team stripes being the same colours as old-fashioned mattresses. During the 1970s they became known as Los Indios. This was allegedly due to the club signing several South American players after the restrictions on signing foreign players was lifted. However there are a number of counter theories which claim they were so named because their stadium is camped on the river bank or because Los Indios were the traditional enemy of Los Blancos —the whites. The latter nickname refers to the club's city rival Real Madrid.