I spent some time in Rio myself, great City! I had a similar situation to you in Columbia. On my way home from a night out some kids in the street kicking a ball around and it lands at my feet. Being drunk, rather than just kick it back I juggle it for a bit then catch it on the back of my neck then knock it back to them (rather impressively considering the drink I had consumed). The kids call me over for a game and I end up playing one on one with this little kid who couldn't have been older than about 14 (I was 23 at the time), we play first to 5, kid has some crazy skills but it's fairly even (mainly due to me pretty much putting him on his **** every time he tries to tackle me) and I think gets to about 3-3 or 3-2 to him.
I was drunk at the time, but I remember clear as day. He sets the ball down on his 'goal line'; (denoted by a line dug out in the street) runs straight at me full speed, I get set to jockey him one way, he steps over the ball, I think I've won it, put a foot in. Nothing, I'm just left standing there on my own. I look behind me and he's standing on my goal line with his foot on the ball grinning at me. Then he goes and does exactly the same thing to me the very next time he gets the ball and its all over.
After it, I felt like he was taking the **** out of me all along, just teasing me knowing that he'd have no probs beating me when he wanted to! The kids walked me back to the hostel I was staying at, I called him 'little Messi' all the way home which they absolutely loved.
Some great memories of travelling involved a football for me now that I think about it!