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The key whistleblower who exposed Russia's alleged scheme to cheat at the 2014 Olympics has filed a motion to dismiss a libel lawsuit brought on behalf of three Russian athletes who were implicated in the doping scandal.

Grigory Rodchenkov's lawyers also filed a lawsuit on Monday against Mikhail Prokhorov, the Russian oligarch who owns the Brooklyn Nets and financially supports the libel suit filed by the three Russian athletes. The lawyers claim Prokhorov's backing of the athletes is simply a way to expose Rodchenkov's location.

Rodchenkov, the former head of the Moscow anti-doping lab and a central figure in the Oscar-winning Netflix documentary "Icarus," is in the U.S. witness protection program and lives in fear of reprisal.

Brooklyn Nets owner Mikhail Prokhorov speaks during an NBA basketball news conference in New York on Jan. 11, 2016. Seth Wenig / AP file

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“With today’s filings, the hunted becomes the hunter," said Jim Walden, one of Rodchenkov's lawyers.

The Russian government has forcefully pushed back against Rodchenkov's claims about a doping program that has been corroborated by international investigators and led to an outright ban of the Russian Olympic Committee from this year's Winter Olympics in PyeongChang, South Korea.

In a statement, Rodchenkov said he was "healthy and well, and also well protected."

He added that "despite Russia's recent disinformation campaign," the claims he made to the International Olympic Committee (IOC) and the World Anti-Doping Agency (WADA) were "completely accurate, and I did not retract a word of it."

The legal action against Prokhorov is known as an anti-SLAPP lawsuit — for Strategic Lawsuit Against Public Participation — that is meant to shield whistleblowers who are sued for libel.

A source familiar with Prokhorov's role previously told NBC News that he is the chief financial backer of the libel lawsuit. After the first of the three biathletes, all women, was stripped of her Sochi medals and banned by the IOC last September, Prokhorov said he would be willing to finance such a suit.

A representative for Prokhorov told NBC News: "We categorically deny the accusations in this suit. But instead of trading in rumors and baseless accusations via the media, we will await our fair hearing in a court of law, where facts and evidence will take their rightful place as the only means of determining the truth."

Rodchenkov has said he gave cocktails of banned steroids to athletes and swapped tainted samples for clean urine on orders from Russian state sports officials. He said that he was instrumental in a Russian government-funded doping program, and that this program allowed Russia to overwhelm the competition during the 2014 Sochi Winter Olympics, where Russia won 33 medals.

Independent investigations by the anti-doping agency and the IOC have backed Rodchenkov's claims. He has been interviewed repeatedly by The New York Times, featured on CBS' "60 Minutes" and profiled at length in "Icarus," a feature-length documentary that won best documentary at this year's Academy Awards.