Germany, 2006. The year the world first saw Messi's greatness on an international stage at his World Cup debut. At just age 18, Messi was the youngest player ever to represent Argentina in a World Cup, when he came on as a substitute with 15 minutes to play against Serbia and Montenegro. Within 13 minutes, he created magic by scoring and assisting in the 6-0 victory. A legend in the making. Messi's career would soon catapult to astonishing heights - redefining what it means to be the greatest.