[1] Lazzari made his professional debut in the Lega Pro for SPAL on 31 August 2014, in a game against Pontedera.

[4] On 29 April 2018, during a match against Hellas Verona, Lazzari was injured in the medial collateral.

[5] He returned to the field on the last day of the championship, in which SPAL avoided relegation by beating Sampdoria 3–1.

[10] Lazzari won his first trophy with Lazio on 22 December 2019, playing the full game in their 3–1 victory over Juventus in the 2019 Supercoppa Italiana, held at the King Saud University Stadium in Riyadh, Saudi Arabia.

[11] Lazzari was given his first senior international call-up for Italy in September 2018, by manager Roberto Mancini, for Italy's opening UEFA Nations League matches against Poland and Portugal later that month.