A calf injury also saw him nearly miss the Champions League final, but he made his return off the bench in Saturday's 4-1 win over Juventus.
Back home at the Santiago Bernabeu, Ronaldo took centre stage as he sung about his own candidacy for the Ballon d'Or, which he claimed ahead of Barcelona foe and five-time victor Lionel Messi a year ago. Ronaldo scored twice in the final, finishing the season with 16 goals in his last 10 games.
Juventus went into the final with an unbeaten record in this season's Champions League and had conceded only three goals en route to Cardiff.
"It will be tough to do better than this year, because we could have done something truly incredible this season", said Buffon, regarded as one of the finest goalkeepers in the history of the game. In the Champions League is a new thing for many of our players.
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These guys are giants, they play at a different level to most of us, and they kept coming back. He added: "I think that is fair (we need to be more clinical)". "Today we've done that".
Madrid completed a sublime double, having won La Liga for the first time since 2012, and the Spanish giants ensured they marked the occasion with joyous scenes raging from Cardiff to the Spanish capital on Saturday night.
Madrid also has Karim Benzema and Gareth Bale in the attack, although there have been rumours of a possible transfer involving them in the near future. "The people that criticise me will need to put their guitar back in the case because once again we won and we are the best", Ronaldo crowed.
For Ronaldo it was a sensational finale to the season which must now end with him winning his fifth Ballon D'Or.
"The players have entered into the legend of Real Madrid and of football, as has our coach", said club president Florentino Perez.
"My age is just a number, I feel like a young boy", said the 32-year-old after being handed the man-of-the-match award by his former United manager Sir Alex Ferguson. "That is why he is already the best coach in the world".