2021: Early career Previously unknown in Algeria, Sedjati came to prominence after achieving notable performances in several Algerian national meetings. On 26 March, at the Algerian Winter Championships in Algiers, he finished second to
Mohamed Ali Gouaned in the
600 meters with a time of 1:17:40. For 800 meters, he also ran 1:45.99 in a Batna meeting on 12 April, defeating
Mohamed Ali Gouaned. The following month, Sedjati finished second behind
Mohamed Belbachir in an Algiers meeting on 7 May, clocking a new personal best of 1:45.86. Sedjati later ran in some French meetings, where he qualified for the
2020 Summer Olympics in the
800 meters after running a personal best of 1:44.91 in
Strasbourg, France, on 16 June. He also ran as a pacemaker in subsequent meetings, helping compatriot
Yassine Hethat qualify for the
2020 Summer Olympics in the same event. Upon arriving in Tokyo to compete in the
Olympic 800 meters, Sedjati and his compatriot
Bilal Tabti both tested positive for
COVID-19 on 24 July and were put into quarantine, forcing them to miss their Olympic event.
2022–2023 At the
2022 World Athletics Championships, Sedjati finished second in the
800m final, clocking 1:44.14 to win the silver medal. At the
2023 World Athletics Championshops, Sedjati made it into the
800m final, but was disqualified due to a lane violation.
2024: Paris Olympics, breaking 1:42 On 7 July, Sedjati won the 800m at the
Meeting de Paris, running 1:41.56 to become, at the time, the third fastest man at the distance, behind
Wilson Kipketer who ran 1:41.11 in 1997, and
David Rudisha, the current world record holder, who ran 1:40.91 at the
2012 Summer Olympics. Sedjati set in the process
a new Algerian national record, replacing the previous record by
Taoufik Makhloufi since the
2016 Summer Olympics by more than a second. Five days later, at the
Herculis Meeting in
Monaco, he won the 800 metres in a time of 1:41.46, thereby improving on his personal best from five days prior by a tenth of a second. Sedjati qualified for the
800 meter final, on 10 August at the
2024 Summer Olympics in
Paris, after missing the event in the previous Olympic cycle due to sickness. He reached the final after winning his race in both the heats and semi-final with times of 1:45:84 and 1:45.08, respectively. Sedjati had remained undefeated in the 2024 season until the Olympic final, where he finished third winning a bronze medal with a time of 1:41.50, behind silver medalist
Marco Arop, who finished in 1:41.20, and gold medalist
Emmanuel Wanyonyi, who finished one hundredth of a second ahead of Arop in a time of 1:41.19. This shifted Sedjati from the third fastest to the fifth fastest man at 800m. ==Personal bests==