Mostafa Smaili gained his first experience at international championships at the African Youth Games in Gaborone in 2014 , where he won the bronze medal in the 1,500 meter run in 3: 47.99 minutes and thus qualified for the Youth Olympic Games in Nanjing , where he was in 3: 46.28 min took fourth place. In 2016 he reached sixth place at the World Indoor Championships in Portland in 1: 52.32 min over 800 meters and then won the bronze medal at the U20 World Championships in Bydgoszcz in 1: 46.02 min. He also qualified for the Olympic Games in Rio de Janeiro , where he reached the semi-finals , in which he was eliminated with 1: 45.78 min. In 2017 he won the Islamic Solidarity Games in Baku in 1: 45.78 minutes and then won the silver medal behind his compatriot Oussama Nabil at the Francophonie Games in Abidjan in 1: 46.73 minutes . He then took part in the World Championships in London for the first time, but was eliminated there with 1: 47.50 minutes in advance .