Lucas Cassius Gatti (born 14 February 1978) is an Argentine football coach and former player.
Gatti played as a midfielder for Argentinos Juniors, Dundee and CD Badajoz.
Gatti was appointed the U23 manager at Bromley in July 2022, having first joined the English side's coaching set up in February of the same year.
On 9 October 2024, Italian Serie D club Olbia announced the hiring of Gatti as their new head coach, replacing Marco Amelia. He resigned just a month later, on 9 November, due to personal reasons.
He is the son of Argentine international goalkeeper Hugo Gatti.