Tunisian Teen Wins Surprise Olympic Swimming Gold

Ahmed Hafnaoui, of Tunisia, reacts after winning the final of the men's 400-meter freestyle at the 2020 Summer Olympics in Tokyo, Japan, on July 25, 2021. Petr David JosekAP

TOKYO—Nobody was watching Ahmed Hafnaoui in lane eight of the Olympic pool.

All eyes were on the Tunisian teenager at the finish.