A former world title challenger has sadly passed away at 68, leaving the boxing community in deep mourning The former featherweight contender went on a stunning 43-fight unbeaten run during his days World Boxing Council and well-wishers have paid their last respects to the California-born fighter The boxing community has been thrown into mourning following the death of former featherweight contender Ruben Castillo, who died at the age of 68. Known for his fearless approach in the ring, Castillo built a reputation as one of the toughest opponents during his era. The boxing community mourns as Ruben Castillo loses life after a prolonged illness. Photo by: YURI CORTEZ/AFP. Source: Getty Images Cause of death Legendary boxer, Ruben Castillo, died of prolonged cancer in Beaumont, Rivers...