The 32-year-old's 74th international goal delivered a win over Russia on Wednesday, meaning a draw against the pointless Kiwis would be enough for the Euro 2016 champions to advance to the last four.
Santos has promised he will rotate his team against the All Whites, with one change enforced due to Borussia Dortmund left-back Raphael Guerreiro's injury, though he did not show his hand when it came to questions about his most valuable asset.
Ronaldo was rested at times by Real Madrid boss Zinedine Zidane towards the end of the season and reaped the benefits as he helped his club secure both the LaLiga and Champions League titles.
Put to him that those in Saint Petersburg and others watching back in New Zealand were excited about watching the forward, Santos told a press conference: "There are many millions who, every time Cristiano plays, are very interested in him playing. He's the best player in the world.
"Everybody wants to watch Cristiano Ronaldo, even I want to watch Cristiano Ronaldo!
"I don't know if I'm going to play with Cristiano or not, I'm not going to tell you anything about the line-up. I don't want the opponents to know. Rotation will take place, that's what I can tell you."
While acknowledging Ronaldo's status, New Zealand manager Anthony Hudson was keen to stress that even without him, the European champions will pose a serious test for his already-eliminated side.
"I think he's the best in the world," Hudson said.
"You take Ronaldo out of the team, you still have some world-class players in there as well. We've seen everything has been tried and it's not one of those where if you deal with Ronaldo then that's it. They have other top players.
"We have a gameplan that we're going to stick to. We're not overawed by it. We're looking forward to it. We're not just going there to play against Portugal and Ronaldo, we're going there to get a result."
Ronaldo might not be the only leading light New Zealand are facing in the coming months.
A return to Russia for next summer's World Cup will only be possible if the All Whites, who must first win the qualifying section in Oceania, can then win a play-off against the team that finishes fifth in South America, which is a spot currently occupied by Lionel Messi's Argentina.
"I don't think it will be Argentina now they have the coach they have," Hudson added, referencing the appointment of Jorge Sampaoli earlier this month.
"We have an incredible amount of confidence that whoever we face, it's the fifth best team in South America. They're fifth for a reason and we'll have confidence going into that game."
