Captain Francesco Totti, Daniele de Rossi, Simone Perrotta and Mancini all scored early for Roma, which has last month handed league champion Inter its only defeat of the Serie A campaign.
Right back Christian Panucci added two second-half goals for Roma.
SPAIN. Sevilla reached the final of Spain's Copa del Rey for the first time in 45 years by beating Deportivo Coruna, 2-0, at home to cruise into the final, 5-0, on aggregate on Wednesday.
Sevilla looks set to meet Barcelona at the final on June 23 at Madrid's Bernabeu on Stadium. Barca takes a 5-2 lead going into Thursday's second leg away to Getafe.
Portuguese midfielder Duda and Uruguayan Ernesto Chevanton scored for Sevilla, which has also advanced to the final of the UEFA Cup, where it faces another Barcelona team, Espanyol.