The 37-year-old, criticised by the coach for his reaction to being substituted against South Korea, saw his replacement, Goncalo Ramos, hit a hat-trick on his full debut in a 6-1 victory.
It was the first time Ronaldo had been left out of the starting XI at a major finals since 2008.
Portugal face Morocco in the quarter-final and, on the role of a man who left Manchester United under a cloud during the tournament, Santos admitted: ‘That is still something that has to be defined.
‘Ronaldo will definitely (be involved), all the players on the bench, if they are not in the starting line-up they can play later.
‘It is important to look at the example of this player’s history, he is one of the best players in the world, being captain – all we have to do is think about this team collectively.’
MORE : Portugal manager reveals real reason why Cristiano Ronaldo was dropped for World Cup clash
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