 His substitute appearance for Chilean club Colo Colo against Santiago Wanderers at the age of fourteen years, nine months and three days smashed the previous record of Frank Lobos considerably.Millán, a precociously gifted attacking player, joined Colo Colo's youth set-up in 2003, and enjoyed a meteoric rise through the ranks.Before his first team debut Millán was promoted to the club's U-17 side, finding the back of the net three times in as many games.