Vidro was drafted in the sixth round of the 1992 amateur draft by the Montreal Expos from Blanca Malaret High School in Sabana Grande, Puerto Rico. He spent four seasons in the minor leagues before making his major league debut on June 8, 1997. He was primarily a reserve infielder for the Expos in 1997 and 1998. Vidro is the first of three players, including Robinson Cancel (New York Mets) and Jonathan Sánchez (San Francisco Giants), from Sabana Grande to make it to the major leagues.