During Manchester United's trip to Craven Cottage in 2009, Danny Murphy featured in an incident with Ronaldo that demonstrated to him the key quality the Portuguese had, that would make him into the footballing icon he is today.
For many players, a trick, a sensational goal or a moment of pure determination would be the quality they would highlight if asked about what makes Ronaldo one of the best players to have ever played the game.
However for Danny Murphy; former Liverpool and Fulham midfielder, a moment of pure madness was what it took to show him that Ronaldo was destined for the history books.
In one particular encounter with the five time Ballon d'Or winner, a game between Fulham and United at Craven Cottage, where the home side were winning 2-0 and heading for a momentous victory, Ronaldo produced an absolute horror challenge against the Liverpudlian.
Thankfully, Murphy was able to dodge the majority of the challenge and assure to the referee that 'no harm had been done'.
Much to Murphy's surprise, Ronaldo kept moaning about the decision to award the home side a free kick, in spite of just nearly being sent off; clearly frustrated that his side were losing.
However upon reflection for his column with the 'Mail on Sunday', Murphy looks back on that particular incident not with malice, but in awe, as he now knows that was the time when he saw the true potential of the Portuguese icon.
In his column, Murphy reflects on the aftermath of the incident, saying: "It infuriated me at the time but looking back I can see it's because he cared so much. Ronaldo was always a talent but when we played United, they had so many great players we couldn't single him out. Though he reached new levels for the last couple of seasons under Sir Alex Ferguson, I never thought he'd go on to achieve what he did for Real Madrid and Portugal."
Murphy continued to praise the Portuguese, and his great rival Lionel Messi, for their extraordinary footballing feats over the years, writing: "For him and Lionel Messi to keep on scoring the amount of goals they do every year is simply phenomenal. He's 33 now but his standards haven't dropped. He has put so much work into being in perfect physical condition."
Ronaldo returns to former club Manchester United with Juventus in the Champions League this week, and he is sure to get a great ovation from the home fans at Old Trafford, even if his actions in the match prove decisive for the result.
Murphy spoke about the Portuguese' return to Manchester in his column, writing: " I'm sure he'll get a big ovation from United fans on his return. " Ronaldo is yet to lose upon his many returns to Manchester.
With 'The Old Lady' looking to finally secure another Champions League crown, Juventus fans will be hoping that Ronaldo destroys hopes at the 'Theatre of Dreams' this Tuesday evening.