Tunisian swimmer Ahmed Hafnaoui, Olympic champion in the 400m freestyle at the Games in 2021, has received a 21-month suspension for three anti-doping whereabouts failures, the Aquatic Sports Integrity Unit said.
"Mr Hafnaoui admitted that he committed three whereabouts failures within a twelve-month period," the body wrote on its website. "His results have been disqualified from 11 April 2024 onwards."
The ban will end on 10 January 2026.
Hafnaoui withdrew from the Paris Olympics last July and August
He won gold in the 400m freestyle at the Covid-delayed 2020 Tokyo Olympics and world titles in the 800m and 1500m in 2023 in Fukuoka, also in Japan.
To facilitate unannounced drugs tests, athletes are required to enter their whereabouts into a software programme.