The Argentina legend believes the Seleccao are over-reliant on their star man and insists they start as underdogs in their Euro 2016 round of 16 tie against Croatia

Portugal are "too dependent" on captain Cristiano Ronaldo and will start as underdogs in their Euro 2016 last-16 tie against Croatia, Diego Maradona believes.

Ronaldo and Co. scrapped through to the knockout stages following their thrilling 3-3 draw against Hungary in Group F on Wednesday.

A brace from Ronaldo not only saw the Real Madrid star become the first player to score in four editions of the European Championships but it helped Portugal set-up a showdown with Croatia in Lens.

But former Argentina international Maradona believes Portugal's reliance on Ronaldo works against them and believes Croatia are favourites heading into Saturday's clash.

"Portugal are too dependent on Ronaldo," Maradona said in a column for the Times of India. "He was brilliant against Hungary, but they are half the force if he doesn't click and the tactically astute Croats will ensure he is low on supply.

"He may have to move around for space and chances of Portugal's success hinge on how well he does that.

"They also have to plug holes in midfield and defence, because these are areas where mistakes may lead to elimination. Croatia start favourites."

Portugal qualified for the round of 16 as one of the best third-placed teams, despite not winning a single game.

Fernando Santos' men drew all three matches against Iceland, Austria and Hungary while Croatia topped Group D after upstaging two-time defending champions Spain on Tuesday.

And Maradona has lauded Croatia as a “tactically sound” outfit and believes experience will play a key part in which side emerges victorious from the game.

"The Croats are a feisty lot as they showed against Spain. They drew after going 2-0 up in the previous game [against the Czech Republic] and conceded early against the defending champs. It could have broken them. But the way Croatia came back to win without stars [Luka] Modric and [Mario] Mandzukic was a testament of steel, resolve and ability," Maradona added.

"The Croats are tactically sound like most European teams, who give nothing away in defence. The specialty of this bunch seems to be the ability to launch counterattacks at great pace with few touches.

"It could be a different experience against Portugal, if Ronaldo's team chooses to play a defensive game and waits to hit on the counter. Croatia have to look to create space in this case and unveil Plan B. With Modric and [Ivan] Rakitic in midfield, expect them to that.

"This lot is perhaps low on flair than the one that won World Cup bronze in 1998, but scores high on tactical discipline, team work and determination. Experience tells me these are valuable traits in knockout games."