The former Milan midfielder was not impressed with the Portuguese captain's showings at the World Cup this summer, and has criticized his attitude as being detrimental to the squad.

Following his triumph over Lionel Messi to win his second Ballon d'Or, many had expected Cristiano Ronaldo to keep up his good form for Portugal during this year's World Cup.

After all, the Real Madrid star had fired his national side into the tournament by scoring a poker against Zlatan Ibrahimovic's Sweden. Despite being placed in a tough group, Portugal were expected to qualify alongside eventual tournament winners Germany, but failed to get out of their quartet, with just one win against Ghana, who finished last.

Former Milan midfielder Zvonimir Boban, who has never been one to mince words, recently took to his column in his native Croatia to criticize the player for what he described as a self-centered attitude that is highly detrimental to his colleagues on the pitch and highlighted his actions both at club and national level.

"[For instance], he scored the [fourth goal to make it] 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," Boban wrote in Croatian publication Sportske Novosti.

Self-centered: Boban feels that the attacker is more concerned about crowning himself in glory rather than the team's progress

"The same thing happened with Portugal in Brazil. There was no order or discipline. 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."

Disappointment: C. Ronaldo endured a torrid campaign in Brazil, in which he scored just one goal and was unable to inspire his side out their group

The Croat has previously slammed other notable footballers, with Rossoneri striker Mario Balotelli oftentimes being the focus of his scorn due to his antics on the pitch.