Despite coming up through the Chelsea academy, Mount always admired Ronaldo during his first spell with the Red Devils from 2003 to 2009.
It was during this period when the Portuguese legend won the first of his five Ballon d'Or prizes and also the first of his six Champions League titles.
And, famously, his free-kick against Portsmouth had kids trying to master his technique for years after.
Incredibly, sitting in the stands that day at Fratton Park was Mount, who is a boyhood Pompey fan having grown up in the city.
Long trips to Chelsea's Cobham training ground would follow when they took an interest in him as early as seven and, by the age of nine Mount had recreated his hero's effort.
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An unearthed clip of a very young Mount shows him talking to the camera before placing the ball down for a free-kick in training.
"I try to base my free-kicks on Ronaldo," a mop-haired Mount explained.
"Hit the ball by the valve and it moves. That's all you do. Top corner, top bins."
And sure enough, the youngster does not miss and the ball flies into the exact spot where he wanted it to.
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Speaking about watching Ronaldo in the flesh at Fratton Park, Mount recalled: "I went as a Portsmouth fan and we lost the game.
"I remember watching Cristiano Ronaldo and he scored this unbelievable free-kick - it was one of the best goals I've ever seen live.
"It was great for me to watch him as one of the best players in the world and that really motivated me as a young boy.
"I remember going to training the next couple of days and trying to recreate the free-kick.
"I was only young so I couldn't really kick it that far.
"But when you watch something like that then you want to add it into your own game.
"It motivates you to practise and try to replicate it in a game situation."
Now Mount might finally get the chance to truly recreate Ronaldo's free-kick as a move to Man United nudges closer.
Chelsea recently turned down a £50million bidfrom the Red Devils but they are open to selling the midfielder after he refused to sign a new contract.
The Blues are asking for closer to £70m but there is room for compromise after Erik ten Hag made the 24-year-old a top target to bolster his midfield.
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As for Mount, any allegiance to Chelsea appears to have been scrapped despite coming up through their ranks and he has already agreed personal terms with United.
Liverpool and Arsenal had been interested in signing the England international - but maybe the allure of copying that Ronaldo goal in the red of United might just have played its part - as long as it is not against his beloved Portsmouth.