[6] Following his spell in Calabria, Baronio was sent to Fiorentina,[7] and continued to develop, firmly considered one of Italy's brightest young talents; yet, he was unable to find a place in the Lazio squad, which at the time was achieving notable success both domestically and internationally.

[2] 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.

[9] 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.

[10] In September 2010 Lega Pro Prima Divisione club Atletico Roma announced to have signed Baronio on a free transfer.

[17] In August 2020, Baronio was hired as a part of newly appointed Juventus head coach Andrea Pirlo's backroom staff.