Tags: Wrestler.
Clemente Marcelino Valencia Nájera (17 July 1968 – 11 October 2011) was a Mexican luchador enmascarado or masked professional wrestler better known by the ring name Doctor X under which he worked for the Mexican professional wrestling promotion Consejo Mundial de Lucha Libre (CMLL) for most of his career winning the Mexican National Welterweight Championship and the Mexican National Trios Championship teaming with Sangre Azteca and Nitro.