injury to the reigning champion, or when a champion stopped working for the promotion, but in the case of the CMLL World Light Heavyweight Championship, there was a storyline reason behind it being declared vacant the first time. In late 2013 the light heavyweight champion Rush was working a long-running storyline rivalry with El Terrible. When El Terrible won the CMLL World Heavyweight Championship, CMLL decided to enhance the rivalry by having Rush voluntarily give up the light heavyweight championship in order to receive a CMLL World Heavyweight Championship match against El Terrible. This allowed CMLL to advance the storyline as well as move the championship off Rush without having Rush lose a match, allowing Rey Escorpión to become the next champion. The second vacancy started on May 22, 2017 when CMLL fired the then-champion Máscara. Rules The official definition by the Mexican lucha libre commission for the light heavyweight division in Mexico is between and . In the 20th century, CMLL were generally consistent and strict about enforcing the actual weight limits. In the 21st century the official definitions have at times been overlooked for certain champions. One example of this was when Mephisto, officially listed as , won the CMLL World Welterweight Championship, a weight class with a upper limit. Although the heavyweight championship is traditionally considered the most prestigious weight division in professional wrestling, CMLL places more emphasis on the lower weight divisions. With twelve CMLL-promoted championships labelled as "World" titles, the promotional focus shifts from championship to championship over time with no single championship consistently promoted as the "main" championship; instead CMLL's various major shows feature different weight divisions and are most often headlined by a Lucha de Apuestas ("Bet match") instead of a championship match. From 2013 until June 2016 only two major CMLL shows have featured championship matches: Sin Salida in 2013, and the 2014 Juicio Final show featuring the NWA World Historic Welterweight Championship. The last time a CMLL World Light Heavyweight Championship match was featured on a major CMLL show was on September 18, 2004, when Último Guerrero successfully defended the title at the CMLL 71st Anniversary Show. Championship matches usually take place under best two-out-of-three falls rules. On occasion single fall title matches have taken place, especially when promoting CMLL title matches in Japan, conforming to the traditions of the local promotion. Outside CMLL, the light heavyweight championship has been defended