Paulo Bento's men enter the tournament on Saturday when they face Germany, while Netherlands take on Denmark in the other Group B fixture.

Nonetheless, the Al Wasl boss is tipping Portugal to crash out at the first hurdle, pointing out that Cristiano Ronaldo is their only player who can make the difference.

"Portugal just about won a qualification playoff to get to the tournament," Maradona told Times of India.

"They recently were booed at home, losing to Turkey. This is despite having the best player on the planet in Cristiano Ronaldo.

"As good as he is with Real Madrid, he often seems frustrated on the national level, as if he was surrounded by players who do little to assist him.

"Coach Paulo Bento has arguably one of the weakest sides in this tournament.

"Ronaldo is the only actual threat. If the Germans can stop Ronaldo, marking him with two or three players, they can also stop Portugal's only offensive threat."