Cristiano Ronado has often described his relationship with Sir Alex Ferguson as a father and son bond.
"He's a fantastic person. A human person. He taught me many things," Ronaldo once told CNN.
"Like I've said before, he's like a father in football, because he taught me many things. I really miss him because I have a great relationship with him."
In the past, Ronaldo has also told stories of how Sir Alex Ferguson helped him in tougher times. For example, when his father was sick in hospital, the former Manchester United manager was insistent he go see him.
"When my dad was sick in London and was in hospital-very bad, in a coma-I had a conversation with [Ferguson]," Ronaldo said. "I said, 'Boss, I don't feel good.'
"We are in a key moment in the league and the Champions League, but I say, 'Boss, I don't feel good. I want to see my dad.'
"[He said] 'Cristiano, you want to go one day, two days, one week, you can go. I'm going to miss you here because you know you are important, but your dad [comes] first."
"When he told me that, I thought, 'This guy's unbelievable. He was a football father for me."
The pair have gone through so much together, especially during their days at Manchester United, but it was during Cristiano's time at Real Madrid that gave us one of the more touching moments.
After winning the European Championships with Portugal in 2016, Ronaldo, as well as Nani, were congratulated by Sir Alex in an emotional embrace.
The Scotsman waited patiently for the players and it was that moment involving Cristiano that got us right in the feels.
Look how much it means to Ferguson to see his former players.
Ronaldo maintains that Ferguson was the man that 'cleaned up his faults' during his time at Old Trafford.
"When I arrived in England I was an 18-year-old kid and had established stars by my side." he told AS.
"Ferguson taught me to clean up my faults, to know to give the pass at the last moment, to take the right decision in the area.
"I spent six years at United and I owe them everything that I am today. I made history at United and won many trophies."
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