Wednesday 17 January 2018 22:28, UK
Grigory Rodchenkov, who revealed state-sponsored doping in Russia, is expected to testify next week at a Court of Arbitration for Sport (CAS) hearing involving the appeals of 39 Russians banned for doping.
CAS, sport's highest tribunal, will examine the cases of 39 Russian athletes who lodged appeals against lifetime Olympic bans imposed by the International Olympic Committee (IOC) over anti-doping violations at the 2014 Winter Games in Sochi.
Rodchenkov and lawyer Richard McLaren, the author of the World Anti-Doping Agency's (WADA) report into state-sponsored doping, have both been announced as witnesses, CAS said in a statement on Wednesday.
Neither will attend the hearing in Geneva, which starts on Monday and will run until January 27 or 28, but they "are expected to testify by videoconference or telephone-conference", CAS added.
Rodchenkov is the former director of the Moscow anti-doping laboratory who fled to the United States in 2016 saying he feared for his life after the sudden death of two senior officials in the Russian Anti-Doping Agency (RUSADA).
He then provided information which led to an investigation of doping at Sochi.
Some of the athletes whose cases are being heard are still hopeful of taking part in next month's Winter Olympics in Pyeongchang, with a final decision on each case "likely" to come between January 29 and February 2 - only a week before the start of the Games.
Russia had originally finished top of the medals table in Sochi, but it has lost 13 of the 33 medals won at the 2014 Olympics, slipping down to fourth following the explosive report based on Rodchenkov's revelations.
The country has been banned from taking part at the 2018 Winter Olympics, which run from February 9 to 25, due to the alleged widespread doping.
However, athletes who prove themselves to be clean have been told by the IOC they can compete under strict conditions, and under a neutral flag.
