The Portugal forward will win his 100th cap in Tuesday night's World Cup qualifier and has unsurprisingly dominated the build-up. Whether that is down to his scintillating recent form or his imminent landmark is debatable but O'Neill is hoping the week ends on a bum note for the Real Madrid man.
Asked what he expected Ronaldo to produce during the game, O'Neill said: "Hopefully very little! I would be happy if he has a really poor game and he is remembered for having a bad night on his 100th cap. It is irrelevant to me that it is his 100th game. It is, of course, a great occasion for the player but it is not a concern for us at all."
He added: "The best hope for us is that the work we have put in is put into practice in the game. We have to recognise the quality of the opposition but we are not sitting here just hoping for Ronaldo to have an off night, we have trained to this level in preparation.
"It is our job to make sure they do have an off night and we can add to them having a frustrating night by taking our opportunity when it presents itself."
Despite his vested interests in a rare slump in form from the 27-year-old, O'Neill remains fully aware of the rare quality he possesses. "I think what Ronaldo has is he is a goal machine as well as creative, I have seen him numerous times, we know where the threat will come from.
"His ability is not just in set-pieces or taking free-kicks but also corners and he is very good in the air, attacking things from the back post area. That is all stuff we have worked on. Can we reduce his possession? Can we get men around him to make life difficult? Of course."
O'Neill, meanwhile, has urged his players to show greater care with the limited number of attacks they are likely to be afforded. Their previous away match - a 2-0 defeat in Russia - saw Kyle Lafferty too frequently isolated up front and his manager hopes lessons were learned.
"There's nine men behind Kyle, the key is getting people up to him at the right times in the game," he said. "When we look back at the game in Moscow, while he looked isolated we didn't have enough control in their half. We could have got ourselves into a good position with better passing.
"It's not a case of giving the ball to him, then letting him hold it up, there needs to be a strong response from wide and midfield players to get into attacking position. We will field a side responsive to that."