Sports' highest court has rejected appeals by 45 Russian athletes plus two coaches who were banned from the Pyeongchang Olympics.
The International Olympic Committee had refused to invite the group of Russians, saying it had evidence of alleged doping in Russian sports.
The Court of Arbitration for Sport handed down its rulings Friday, less than nine hours before the opening ceremony.
A vetting process was designed to exclude Russian athletes from the games if IOC officials weren't sure they were clean, even if they hadn't been banned for doping.
An additional 168 Russians had been invited as "Olympic Athletes from Russia," competing in neutral uniforms under the Olympic flag.