Switzerland's Patrick Baumann was appointed head of the IOC commission monitoring candidates for the 2024 Olympic Games on Tuesday, replacing Frankie Fredericks, who stood down earlier in the day.

Fredericks, who on Monday was also replaced on an IAAF taskforce investigating Russian doping, has been embroiled in a corruption scandal related to the awarding of the 2016 Games to Rio.

But the former Olympic medallist sprinter denies any wrongdoing in having accepted nearly $300 000 from a sports marketing company the day that Rio de Janeiro was awarded the 2016 Olympics.