WADA last December handed down a four-year package of sanctions on Russia after it found the country had manipulated and tampered with data at the Moscow Laboratory.

If sport's highest court upholds WADA's decision, Russia's flag and anthem will be banned from the postponed Tokyo 2020 Olympics next year and the Beijing 2022 Winter Games.

Russia could also be stripped of World Championships it has been awarded.

The country has been barred from bidding for the 2032 Olympic and Paralympic Games.

There would be a route to competition at major events for Russian athletes who can prove they had no involvement in the doping scandal that emerged in the wake of the Sochi 2014 Winter Games or the subsequent cover-up.

International Federations, in conjunction with WADA, would decide which Russian athletes can compete.

The sanctions were approved by the WADA Executive Committee after an investigation alleged data from the Moscow Laboratory was intentionally altered prior to and while it was being forensically copied by WADA in January 2019.

Access to the Moscow Laboratory data was key to WADA's decision to controversially reinstate RUSADA after it had been declared non-compliant in 2015.

The data was required to determine more Russian drugs cheats while potentially clearing others.

WADA President Witold Bańka has said the organisation is convinced the sanctions announced last December was the correct decision.

"WADA has left no stone unturned in preparation for this hearing and we are looking forward to having the opportunity to present our case clearly and fairly to the panel," Bańka said.

"I remain convinced that the WADA Executive Committee made the right recommendation in this case last December.

"As at every other stage, we are following due process in relation to RUSADA’s compliance procedure as we continue to deal effectively with this complex matter."

Former RUSADA director general Yuri Ganus, who was removed from his post in August, has claimed RUSADA has "no chance" of winning its appeal.

RUSADA's acting director general Mikhail Bukhanov disagrees, telling insidethegames the organisation believes it has some "really strong positions and arguments".

The CAS hearings are due to run until Thursday (November 5).

Due to COVID-19 restrictions, they will take place in a mixed format with parties, legal representatives and witnesses attending either in person or virtually, via a video link.

WADA had requested that the hearing be held in public but for that to happen all parties were required to be in agreement and that was not the case.

The arbitral panel is set to comprise Judge Mark L Williams of Australia, Italian Prof Luigi Fumagalli and Dr Hamid G Gharavi of France and Iran.

The International Olympic Committee, International Paralympic Committee, Russian Olympic Committee, Russian Paralympic Committee, Russian Ice Hockey Federation, International Ice Hockey Federation, European Olympic Committees and several Russian athletes have been admitted as intervening parties.