After playing for several clubs in his country, mainly Udinese, he finished his professional career in Spain, where he represented Racing de Santander and Córdoba.
Born in Viareggio in the Province of Lucca, Tuscany, Pierini began his professional career with Udinese, making his debut in 1991 and moving on loan to Fidelis Andria four years later.
[4] After only five La Liga matches he was released in the next transfer window and signed with Córdoba in Segunda División,[5] being relegated in that season and promoting in his third, always as an undisputed starter.
[6] Pierini made one appearance for the Italy national team, playing in the 1–2 friendly loss to Argentina at the Stadio Olimpico in Rome on 28 February 2001.
[7] In July 2009, with Córdoba consolidated in the second level, Pierini retired from playing at the age of 36, but stayed connected with his last club, immediately being named its assistant manager.