Ronaldinho wrote an open letter to his younger self on The Players' Tribune.
In it he talkes about growing up without his father as well as various other aspects of his life as a young player.
One of the most relevant parts to Barcelona was the advice he gave to Lionel Messi.
He wrote: "At Barcelona, you’ll hear about this kid on the youth team. He wears number 10 like you. He’s small like you. He plays with the ball like you.
"You and your teammates will go watch him play for Barcelona’s youth squad, and at that moment you’ll know he’s going to be more than a great footballer. The kid is different. His name is Leo Messi.
"You’ll tell the coaches to bring him up to play with you on the senior side. When he arrives, the Barcelona players will be talking about him like the Brazilian players were talking about you.
"I want you to give him one piece of advice. Tell him, 'Play with happiness. Play free. Just play with the ball'. Even when you are gone, the free style will live on in Barcelona through Messi."