[1][2][3][4] He made his debut in the Argentine Primera División, playing for Lanús on 3 March 2002 when coach Carlos Aimar sent him on the field at half-time in order to replace Santiago Hoyos in a 1–1 with Estudiantes.

[8] In the second half of the season he scored another four goals in four victories against Rosario Central, Tiro Federal, River Plate and Newell's Old Boys but also received a red card in the game with the latter and another one with Estudiantes.

[12] Fabbiani made his Liga I debut under coach Ioan Andone on 1 August in a 1–0 away win over Oțelul Galați in which he provided an assist for a goal scored by Didi, which was eventually cancelled by the referee.

[1][20] In the next season he played only in the first round for CFR, managing to score the final goal of the 4–0 victory with Otopeni, shortly afterwards being loaned to Argentine club Newell's Old Boys.

[26] His transfer caused a stir among River Plate supporters, which inspired the musician Javier Montes, who was a fan of the team to compose a song for him called La Banda del Ogro (English: The Band of the Ogre).

[1][3] Fabbiani spent the last years of his career playing in the fourth league of Argentine football at Deportivo Merlo, with a short 2018 interruption at Liga Panameña de Fútbol club, CD Universitario, announcing his retirement in October 2020.

[35][36][37][39] In February 2024 he went back to coach Deportivo Riestra, this time in the Argentine Primera División, making his debut in a 3–0 home loss in front of River Plate.