Brosco is a product of the
Roma youth system. His favoured position is at
centre back but he is also able to score goals with his good heading ability. At the age of 17 he became a key member of Roma's U20 side that finished as runners-up in the U20 cup tournament. He has captained the youth side on many occasions. Brosco was on Roma's bench in several games in the 2008–09 season.
Triestina Brosco was loaned out to
Serie B club
Triestina on 5 August 2009 and got his senior debut in a Coppa Italia match on 16 August 2009. His league debut came five days later in a scoreless draw against
Mantova. In June 2010 Triestina excised the option to sign him in
co-ownership deal for €100,000. In June 2011 Triestina acquired the remain 50% registration rights for €500.
Pescara In the summer of 2011, he was bought by
Parma for €200,000, which decided to send him to
Serie B club
Pescara in another co-ownership deal for €100,000. On 10 September 2011, he made his debut with Pescara in the home match won 2–0 against
Crotone. He moved on loan to fellow Serie B club
Ternana on 31 August 2012, along with
Riccardo Maniero and
Antonino Ragusa. In June 2013 Parma bought back Brosco for €500.
Latina Brosco returned to Parma in June 2013. In July 2013 Brosco was signed by another Serie B club
Latina in temporary deal, along with
Alessandro Iacobucci. In June 2014 Latina did not excised the option to purchase both players; however on 10 July 2014 Brosco was signed by Latina in 4-year contract.
Verona On 31 January 2017, he was sold to
Verona. Verona loaned him back to Latina until the end of the 2016–17 season.
Ascoli On 24 July 2018, Brosco signed with
Ascoli.
Vicenza On 20 July 2021, he signed a two-year contract with
Vicenza.
Return to Pescara On 30 August 2022, Brosco returned to
Pescara, now in
Serie C. ==International career==