Baronio was sent on loan to hometown club Brescia, for the 2008–09 season, and was a key player in the "rondinelle"'s promotion push, ultimately losing to Livorno in the playoffs. At the end of the season, he returned to Lazio with the intention to reclaim a first team place following the departure of coach Delio Rossi and the appointment of new boss Davide Ballardini, who promptly presented him as a regular in the successful 2009 Supercoppa Italiana game against Inter and later also in the following Serie A league games, partially due to Ledesma was frozen by the club for contract dispute. After the dismissal of Ballardini and the appointment of Edy Reja as new head coach, Baronio found again limited space in the first team and left Lazio on 30 June 2010 after his contract expired.