World Cup arbitrator Mark Geiger has "completely" denied he requested Portugal chief Cristiano Ronaldo's shirt at half-time in the Morocco amusement.
Fifa said it "unequivocally" censures the claim, apparently made by Morocco's Nordin Amrabat after their 1-0 vanquish.
Watford winger Amrabat said Ronaldo's partner Pepe let him know of the demand.
Fifa said Geiger "emphatically discredits these cases", including the American had "acted in a model and expert way".
Ronaldo scored the victor on Wednesday, as the European champions thumped Morocco out of the competition.
Addressing Dutch TV, Amrabat supposedly stated: "I don't comprehend what [the referee] is utilized to, yet he was extremely awed by Cristiano Ronaldo.
"What's more, I get notification from Pepe that he asked in the principal half on the off chance that he ought to have his shirt."