Ronaldo was given a two-game suspension on Wednesday for kicking Cordoba defender Edimar during Real Madrid's 2-1 victory in La Liga last week, and as the Portuguese forward left the field, he brushed the crest on his right breast, as if to polish it.
Real Madrid won the Club World Cup for the first time in their history on December 20 with a 2-0 victory over San Lorenzo in Morocco.
Djukic labelled Ronaldo's violent conduct against his players - he also appeared to slap Edimar as the defender fell, before fending off Jose Angel Crespo with a forearm to the defender's face - as "an act of desperation", while the Serbian coach was unimpressed by the aftermath.
"[Ronaldo's] gesture to his badge...was ugly and conceited," Djukic told Marca.
"He shouldn't have done that because it is not becoming of the best players in the world, who are him and [Barcelona's Lionel] Messi."
Djukic added that Cordoba did well to keep Ronaldo quiet last Saturday, which meant the Portugal international "wasn't feeling good. That's what caused the whole thing, because of the desperation he felt".
