AC Milan star Boateng walked off the field, prompting his team-mates to do the same, following racial abuse from Pro Patria fans on Thursday.
FIFA supremo Sepp Blatter initially blasted the midfielder’s actions, labelling his decision to leave the pitch as “running away”.
But superstar Ronaldo claims Boateng’s decision was a personal one that was his alone to make.
The Real Madrid ace said: “Why this racism is still happening is incredible.
“I think it was a very personal decision by him — if he’s very angry, if he’s sad, if he’s feeling particularly sensitive, then that’s his decision. It depends on how you are feeling at that moment.
“We have to deal with these people in the stadium — perhaps they have a screw loose.”
Former Barcelona boss Pep Guardiola also backed Boateng’s decision and reckons it could deter racists in the future.
The Spaniard said: “Maybe it was a good step to take. Maybe with Milan dealing with this situation in that way means that it won’t happen again.”
Barca star Andres Iniesta added: “The sad thing is that these things actually do happen. It is a very sad thing and a personal reaction by him.”