Born in Cantù but growing up in Ischia, Brienza began his footballing career with local club Campagnano, before moving to Florence at the age of 15 to play for Isolotto.

In the 2004–05 Serie A campaign, Brienza scored an impressive 10 goals in 33 games playing just behind Luca Toni, earning a call-up to the national team.

Following Francesco Guidolin's return to Palermo in the 2006–07 season, Brienza failed to find a stable place in the regular lineup, being featured mostly as a substitute, playing only 22 league and five UEFA Cup matches.

On the 37th matchday, after a 2–1 home win to Siena, Guidolin declared his choice to use Brienza mostly as a reserve as one of his main mistakes in a troubled season which ended in a fifth place.

[5] Brienza, who originally declared his intention to leave Palermo to find more space in the lineup, remained for the 2007–08 season, later stating to have changed his mind following a meeting with new boss Stefano Colantuono.

[9] He helped the club to win an immediate return to the top flight and established himself as a first choice in the 2011–12 season under the guidance of new head coach Giuseppe Sannino, who regularly featured him as attacking midfielder.

[18] In November 2022, 43-year-old Brienza went out of retirement to join hometown club Ischia in the Eccellenza fifth-tier amateur league, with the aim to help them win promotion to Serie D.[19] He left the club by the end of the season after being part of Ischia's squad that won promotion to Serie D. In 2005, Brienza was called up to the Italy national team by Marcello Lippi and was subsequently capped during a friendly North-American tour with the Azzurri, marking his debut in a 1–1 draw with Serbia and Montenegro at Rogers Centre, Toronto on 8 June 2005, replacing Giorgio Chiellini in the 64th minute.

Brienza and Toni were replaced by Cristiano Lucarelli and Antonio Langella at half-time in the 1–1 draw at Giants Stadium, East Rutherford, New Jersey state.