In 1482, together with the Colonna, he fought against Girolamo Riario, nephew of Pope Sixtus IV, who excommunicated Antonello.
His Lazio fiefs of Albano, Castel Savello, Castelgandolfo and Ariccia were besieged and captured by Paolo Orsini.
Antonello replied by attacking the Orsini fief of Marino, but was defeated and wounded.
He sued a peace with the Pope, but when the latter died in 1484 his support to the election of Innocent VIII granted him the role of Papal general in the war against the Kingdom of Naples.
He died the following year for a wound received in the baronial war against the Orsini.