He went 13 - 0 ( 13 KO 's ) his first year in the ring .
Gardner began his career as a professional boxer on 12 December 1948 , in a novice tournament , winning all of his fights by knockout in the first round .
Gardner went 13 - 0 ( 13 KO 's ) Gardner 's first year in the ring .
Gardner began his career as a professional boxer on 12 December 1948 , in a novice tournament , winning all of his fights by knockout in the first round .