Cornell University Athletics

Mabley was a three-year letterman in lightweight crew (1963-64-65). He stroked the lightweight varsity crew to three straight Eastern Sprint titles, with the 1964 (4-0) and 1965 (4-0) crews going undefeated. The 1964 varsity was the first perfect season in Cornell lightweight history. The 1963 and 1965 varsity boats competed at the Henley Royal Regatta, with the 1965 boat losing in the semifinals of the Thames Challenge Cup. He was commodore of the lightweights as a senior.