Portugal's coach Fernando Santos says Cristiano Ronaldo's two-goal display against Hungary proves he has shaken off a poor start to return to his best at Euro 2016.

Ronaldo scored a pair of brilliant goals in Lyon on Wednesday to go down in European Championship history as the first player to score at four finals.

Portugal came from behind three times for a 3-3 draw which allowed them to scrape into the last 16 to face Croatia in Lens on Saturday, although they will only have two days' rest.

Ronaldo, Portugal's most-capped player ever with 128 appearances, rescued his country and wracked up another record by making a 17th appearance at a Euro finals, overtaking France's Liliam Thuram and Dutch goalkeeper Edwin van der Sar.

"This is what Cristiano is all about, because he’s a winner and a scorer, he feeds on goals," said Santos.

"This will have increased his confidence levels. He’s a confident player anyway, but this will have boosted him for the next game against Croatia."

The 31-year-old opened his account in style with a deft backheel on 50 minutes, then netted with a powerful header 12 minutes later as he twice equalised at the Stade de Lyon.

Ronaldo had struggled as Portugal drew their other Group F games against minnows Iceland and Austria, when he hit the post with a second-half penalty on Saturday.

- Unwanted opponents -
Santos says Portugal must now raise their game against a team he had not wanted to play.

"Croatia are one of the sharks, we had been trying to avoid them," admitted the Portugal boss.

"They placed first in a group with Spain, which tells you all you need to know about them.

"The most important thing is that we are through to the knock-out stage.

"We had wanted to finish in first place, to move on, but not like this."

The 61-year-old was relieved his side had rediscovered their goalscoring touch after converting just one of their 50 shots on goal against Iceland and Austria.

After 37-year-old Zoltan Gera's superb opening strike gave Hungary the lead, Nani levelled for Portugal just before the break following Ronaldo's superb pass.

Hungary captain Balazs Dzsudzsak then twice restored the lead for the 'Mighty Magyars' only for Ronaldo to level for Portugal each time in a frantic second half.

But Portugal's defence, marshalled by Pepe, looked less than solid in what was an obvious cause for concern for the manager.

"I think over the three matches we played more than enough to finish in first place," said Santos.

"We hadn’t been able to score and we weren’t convincing up front. Then we managed to score and we had chances to get more goals.

"We weren’t as tight in defence as we were before, we conceded a goal off a rebound, but that can happen.

"I have to praise my players, they responded three times when we were out.

"We tried to score the fourth goal, but maybe we were too cautious late on.

"If we had to choose between qualifying or taking unnecessary risks and going home, then we achieved what we set out to do."

If Portugal beat Croatia on Saturday they would face either Switzerland or Poland in a quarter-final in Marseille on June 30.

"We only have finals now, they will be hard fought and I think we will come out on top at the end," said Santos, who has said he expects to reach the final in Paris on July 10.

"We attack a lot more, but we’re weak defensively, so we need to find the 1,000,000 euro answer (to achieve a balance).

"The group is in an amazing mood, there is huge will to win.

"The players have huge expectations, because we want to reach the final and win it."