Río Cuarto, Córdoba
Born in Río Cuarto, Córdoba, Pereyra began his professional career at Club Atlético River Plate, helping the club to four Primera División titles during his spell there. In January 2004 he was transferred to RCD Mallorca in Spain, eventually becoming an undisputed starter for the La Liga side and making his debut in the competition on 8 February by coming on as a 63rd minute substitute in a 0–3 away loss against Sevilla FC.