Tossi began his career with Colegiales.[2][3] After twenty-three appearances in three seasons, which included his senior bow versus San Telmo in April 2013, Tossi netted his first goal during a 2–0 win over Brown on 25 October 2014; another goal followed six days later versus Deportivo Merlo, as he scored twice in five games in 2014.[2][4] Ninety-three matches and five goals occurred in four further seasons with Colegiales.[2][5][6] In July 2018, Tossi joined fellow third tier club Comunicaciones.[2] His first goals arrived in the succeeding December versus Sacachispas and Tristán Suárez.[2][7]
