"When you talk about professional footballers, rightly or wrongly, people often already have an idea in their head about what they're like. Gareth, especially with that kind of attention, you could forgive for changing a little bit. But honestly? For the four or five years I've been with him he hasn't. It doesn't float his boat all the attention he gets. He's very much for his wife and his children, his family in Cardiff. That is his universe.
"The football comes natural. It's not something he is using to facilitate a superstar lifestyle. He just genuinely loves being on pitch."
And does this relentlessly positive and encouraging demeanour also take pressure off his team-mates? "Yes," said Coleman. "That's why he has got so much respect of the players because he's not like that."
Having largely succeeded in negating Eden Hazard on Friday, the tactical challenge now for Coleman is how to restrict Ronaldo following a sixth straight season at Real Madrid during which he has scored more than 50 goals, despite whispers that he may be past his peak.
"I could work the defenders for the next month, drilling them about Cristiano Ronaldo, but he has the capability to do something special," said Coleman. "That's the danger. But we have got one in our team [Bale]. It balances itself out. We will just concentrate on what we're good at. That's our identity."
Coleman is also certain that Bale will not be distracted either by the focus on him or the knowledge that, should Wales prevail, he could go a long way to challenging Ronaldo and Lionel Messi for the 2016 Ballon d'Or.
"I don't think that's in Gareth's head," said Coleman. "They are two of the best players on the planet who know each other very well. There won't be any love lost on the evening for both teams, not just Gareth and Cristiano.
Any friendship will have to wait until after the game."