 In the first half of 2009–10 season he often partnered with Bocchetti but in January faced competition in new signing Dario Dainelli while the team's coach preferred a 3–5–2 formation with 3 central defenders and 2 wing-backs.On 1 February 2010, Biava joined Lazio for a transfer fee of €800,000 (including other costs Lazio paid a total of €1.04 million).Along with new signing André Dias, he became the backbone of the Lazio team starting in 11 matches in the second half of the 2009–10 season and helped the club survive the relegation battle.