Cristiano Ronaldo spent six successful years playing under legendary manager Sir Alex Ferguson at Manchester United.
Together the pair won a staggering three Premier League titles, the Champions League and the FA Cup, with Ronaldo also picking up a Ballon d'Or in 2008.
Ronaldo credits Ferguson as the man who helped turn him from a boy into a man after spotting his potential as a teenager at Sporting Lisbon. And Ronaldo owes the Scot a great deal in regards to the success he has enjoyed.
But it's not just in a football sense that Ronaldo rates Ferguson as the greatest coach he ever came across. It's also in the way in which he helped him during a difficult time in his life, when his dad was very unwell in hospital.
Speaking on the Jonathan Ross show in 2015 - six years after he left United for Real Madrid and 10 years after his dad passed away - Ronaldo explained how Ferguson's understanding nature changed their relationship.
He said: "In terms of personal stuff I just have to say, 'Thank you for what you did for me.'
"Especially, I remember, the thing that is in my memory, the time my father was sick in hospital and we were in a tough moment in the season.
"We had important games in the Champions League and league, and I said 'Coach, I need to go and see my daddy'.
"And I was a key player, a very important player. And he said 'Listen your family is the most important thing you have in your life.
"If you want to go three days, four days, five days, you can go.'
"This moment is what I keep with me, because it was the most important moment of my life. He shared it with me and this is why I respect him.
"And for me he is the best coach I ever had."
