San Luis Potosi, Mexico — Rafael Martinez remained perfect on the NASCAR Mexico season as he picked up his third victory in as many races Sunday before a record crowd of approximately 10,000 at the Autódromo Potosino. Martinez qualified fourth and led in the early stages of the 120-lap event on the 1/2-mile oval before being passed by Germán Quiroga. Quiroga, though, ran into trouble just past the 100-lap mark when a lapped car blew a motor and Quiroga spun in the oil. The next event is May 20 at Monterrey. Race No. 3 5/6/2007 Autódromo Potosino San Luis Potosi, Mexico