LONDON — The International Olympic Committee’s handling of Russia’s systemic doping program has been plunged into disarray after sport’s top court overturned bans issued to 28 Russian athletes just days before the start of the Winter Games in Pyeongchang, South Korea.

The Court of Arbitration for Sport ruled Thursday that there was insufficient evidence that the athletes — including some medal winners — breached anti-doping regulations at the 2014 Olympics in Sochi, Russia. The reversal means athletes deemed to have been part of an elaborate cheating scheme may yet compete in the Olympics. It is yet another blow to the credibility of the Olympic committee’s management of the doping affair.

In a move criticized by many in the global anti-doping community, the IOC ruled that clean Russian individuals could compete in separate uniforms designating them as “Olympic athletes from Russia,” should they satisfy a review panel.

On Tuesday, 169 athletes from Russia were cleared to participate, making the contingent one of the largest at the games, and just eight short of the 177 sent to compete in Vancouver, British Columbia, in 2010.

— The New York Times