How much did the Messi-Ronaldo rivalry drive them both?

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They were two iconic shirt celebrations that came to define a rivalry like no other - but how much did Lionel Messi. Cristiano Ronaldo drive each other?

Hear from leading journalists on how two of football's greatest players reached unprecedented heights.

Watch Rivals: Messi v Ronaldo now on BBC iPlayerandlisten to Sporting Giants: Messi v Ronaldo on BBC Sounds.