Ronaldo, who left Manchester United to join Real Madrid in 2009, is set to line up against his former club for the first time in the first leg of the last-16 tie later this month.
The 28-year-old Portugal international is still full of respect for the Red Devils boss and insists he enjoys an “excellent” relationship with the Scot.
“I still have an excellent relationship with [Ferguson] and it will be nice to see him again,” said Ronaldo. “He taught me the basis of football.
“I arrived in Manchester when I was only 18. He managed my career in the best possible way and for me he is one of the most important people in football.”
Ronaldo scored 118 goals in 292 appearances for the Red Devils, winning three Premier League titles and the Champions League, before completing a world-record £80m transfer to Real Madrid in 2009.
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