Lucas Ezequiel Viatri (born 29 March 1987) is an Argentine footballer who plays as a striker for Estudiantes.
Viatri started his playing career with loan spells with Emelec of Ecuador and Unión Atlético Maracaibo of Venezuela. He returned to Boca Juniors in 2008.
On May 17, 2008 Viatri made his debut with Boca in a game 2–1 victory over Racing Club. In August 2008 he was part of the squad that won the 2008 Recopa Sudamericana. Subsequently, during the Apertura 2008 he was a regular on the first team and helped them get the championship title by scoring 8 goals, one of them at the Superclásico.
On July 2, 2014, Viatri transferred to Chinese Super League side Shanghai Shenhua. On July 15, 2014 Viatri made his debut with Shanghai Shenhua in a China FA Cup game against Chongqing Lifan, he scored twice and made an assist to help the super league side won 3-0. Six days later, Viatri scored twice again to let Shenhua won 3-2 against Liaoning Whowin in a Chinese Super League game.