The Reds boss is impressed with the character of players from that part of the world and recently raided Chile for exciting teenage striker Angelo Henriquez.
"Our scouting there has increased," Sir Alex reveals in this month's Inside United. "We've got an operative in Mexico, two in Brazil and four South American scouts now.
"Quite frankly, they do produce. The South Americans love playing football, it's just in their blood. The three Brazilians - Anderson, Rafael and Fabio - love it and are first to training every morning. It's a breath of fresh air.
"Antonio Valencia is as tough as nails with great discipline about him. Chicharito has a fantastic attitude to playing and everything else. It's really good. We've done very well in Central and South America in the last two or three years."