Lostress was the trio with which Leonardo took his first steps as a jazz pianist and composer (2002-2009). Initially formed with Marco Balsimelli on bass (later replaced by Emiliano Amaddii) and Simone Duranti on drums, the trio primarily performed original compositions as well as arrangements of jazz standards, occasionally venturing into free improvisation.

Their compositions were far from conventional, embracing a more creative and stylistically elusive approach that blended various influences beyond traditional jazz structures.

The trio performed at numerous festivals and clubs across central Italy, collaborating with artists such as saxophonist Daniele Malvisi and contemporary dancer Katia Frese in the theatrical/musical show Feblus.