Champions League
The player represented the likes of Barcelona, Inter and AC Milan during his career but never got the chance to play for Manchester United.
Cristiano Ronaldo, Karim Benzema, and Jude Bellingham have flourished at Los Blancos, but not everyone fared so well.
Carlo Ancelotti was forced to personally step in to ensure Real Madrid legend Toni Kroos was signed.
He would have 'head-to-head' duels with Messi when they were in the same age group - but only one of them made it at Barcelona.