Sidney Jose de Siqueira Santos (born 22 July 1987) is a Brazilian former professional boxer who competed from 2005 to 2017. He is a former Conselho Nacional De Boxe (CNB) lightweight champion.
Siqueira began his career with a loss to Andre Marcos Nascimento, but rebounded with an eight-fight winning streak. During that run, he avenged the defeat against Nascimento, defeating him in their second meeting to capture the vacant Brazilian (CNB) lightweight title.
Siqueira notably faced future five-division world champion and three-division undisputed champion Terence Crawford, suffering a knockout loss in November 2012 at the Wynn Las Vegas. On 17 January 2014, he challenged Marcelino Nicolas Lopez for the WBC Latino lightweight title, but was knocked out in the third round. On 12 December 2015, Siqueira faced WBA interim lightweight champion José Benavidez Jr. in a non-title bout, losing by unanimous decision.
Siqueira retired with a professional record of 26âÂÂ13âÂÂ1.