Drogba is a doubt for Ivory Coast with an elbow injury.
But Portugal and Real Madrid star Ronaldo said: "It will be a battle against Ivory Coast.
"Like most African teams they're a big, quick, physical team - and, of course, the have the mighty Drogba.
"To stop Drogba, the defence will have to be on their toes. Like any great striker if you switch off he will punish you, but no man is unstoppable."