In the build-up to the Champions League quarter-final second leg between Real Madrid and Atletico Madrid, a lot of people noticed how Cristiano Ronaldo was singing the famous anthem.

Whilst everyone loves the Champions League anthem, its pretty rare to see any players, especially a high profile player like Cristiano Ronaldo, singing it.

But, it was clearly such a big game that Cristiano Ronaldo was keen to psyche himself up and perhaps the Real Madrid superstar knows the words!

What do you think about this video?