Ukrainian skeleton racer Vladyslav Heraskevych's disqualification from the Winter Olympics over his helmet depicting fellow athletes killed since Russia's full-scale invasion is the Games' biggest controversy so far.

Heraskevych was barred from the men's skeleton in Milan-Cortina earlier this week after he refused to stop wearing it and on Friday his appeal was denied.

He has said those featured on his helmet include teenage weightlifter Alina Peregudova, boxer Pavlo Ishchenko, and ice hockey player Oleksiy Loginov, adding that some of them were his friends. More than 20 athletes appear on the helmet in total — here's more on each of them.