Mezue ahịrịokwu na-esonụ: N'ụbọchị nke anọ, Dressel nọ n'ọnọdụ nke abụọ n'ozuzu ya na prelims nke
100 mita freestyle na oge nke 47.73 ma gafere na ọkara ikpeazụ. N'ụtụtụ na-esote asọmpi ahụ, ọ gbagoro na 47.23 na okpomọkụ ọkara ya wee ruo ọkwa ikpeazụ nke abụọ maka okpomọkụ ọkara. Dressel nwetara ihe nrite ọlaedo mbụ ya n'egwuregwu Olympic na njedebe nke 100 mita freestyle na oge nke 47.02, ihe ndekọ Olympic ọhụrụ. Dressel ji narị isii nke sekọnd n'ihu onye Australia bụ Kyle Chalmers, nke bụ mgbanwe nke onye mmeri Olympic site na 2016 Summer Olympics ebe Chalmers meriri nrite ọla edo na Dressel mechara nke isii na 100 mita freestyle.