Once it became apparent that the Portuguese was looking to take on a new challenge, his agent was charged with the task of finding a potential buyer.
With Jorge Mendes having previously conducted business with Napoli, they were among his first ports of call.
Ronaldo has claimed on a number of occasions that Juve were always his preferred option when pushing for a switch away from Real Madrid.
The five-time Ballon d’Or winner could, however, have ended up in a different Italian destination had the figures involved in a stunning deal not forced one party from the negotiating table.
Giuntoli told Sky Sports Italia: "We [Napoli] have a close relationship with Jorge since [Faouzi] Ghoulam's contract renewal and we often speak to him.
"I was with [Napoli chairman Aurelio] De Laurentiis when he made the offer to us.
"We went quiet and upon going into the details of the operation we realised that it was out of our reach."
As Napoli walked away, the door was left open for Juve to make their move.
They were able to complete a marquee signing, with the reigning Serie A champions securing a prized asset despite initially doubting that a deal could be done.
Their sporting director, Fabio Paratici, told reporters at the Dubai International Sports Conference: “It all happened very quickly. It was a historic transfer, and we need to thank the president and Real Madrid because selling a player like that isn’t easy.
“The first contact was in the Champions League quarter-finals, Jorge Mendes told me that Cristiano Ronaldo wanted to sign for Juventus.
“I thought it was a joke, then we met to discuss Cancelo and he brought Ronaldo up again. At that point, I realised we could try, and I went to talk to [president Andrea] Agnelli.
“It wasn’t easy, but he was immediately positive from a technical point of view, as well as the player’s motivation and what he could bring to our brand.
“After a few hours, he called me back and told me to try.”
Paratici added on Massimiliano Allegri’s reaction to being informed that a move for Ronaldo was something the club were considering: “When I told the Coach he was very happy, he’s a lucky coach.
“Allegri talked about it with the commercial directors, we looked at the numbers and decided it would be advantageous to proceed.”