Portugal were eliminated from Brazil 2014 at the first hurdle as they finished third behind eventual World Cup winners Germany and the United States in Group G.
Ronaldo was troubled by knee problems throughout the tournament and the Portugal captain appeared discontent with his team-mates after he stormed off the pitch following the country's last-gasp 2-2 draw with the USA.
And Boban - a 51-cap veteran for the national team and a four-time Serie A winner with Milan - said the 29-year-old's individual mentality was the reason behind Portugal's failure in Brazil, pointing to his behaviour after scoring the final goal in Real Madrid's UEFA Champions League triumph over Atletico Madrid in May.
"Ronaldo is an amazing player and he showed that again in Brazil, even if he missed a number of chances," Boban wrote in his column for Croatian newspaper Sportske Novosti.
"But his biggest flaw is the way he looks at himself and the team.
"He scored the [goal for] 4-1 in the 120th minute of the Champions League final and celebrated like he was insane. That was the ultimate proof that he loves himself. The headlines should be about the team, not about Ronaldo.
"The same thing happened with Portugal in Brazil. There was no order or discipline. All the Portugal players were playing their own game and more occupied with their hair and tattoos. It's Hollywood behaviour.
"It's almost as if the players wanted to show there's more to Portugal than Ronaldo. It's a sad thing that a team loses its identity because of an unbalanced captain, both for Ronaldo and for an entire generation."
