Rio De Janeiro, Apr 3 (Reporter) Uruguayan forward Gonzalo Mastriani scored twice as Brazilian side Athletico Paranaense cruised to a 4-1 away win over Paraguay's Sportivo Ameliano in their Copa Sudamericana opener on Tuesday. Mastriani netted either side of goals from Bruno Zapelli and former Manchester City midfielder Fernandinho while Fredy Vera was on target for the hosts. "We found it difficult in the first half but we changed our system at halftime and that made a difference," newly-appointed Paranaense manager Cuca told reporters. "I came here to get the best out of these players and try to win trophies. That's our objective." In other Copa Sudamericana fixtures on Tuesday, Argentinos Juniors won 3-2 at Nacional Asuncion, Belgrano was held to a goalless home draw by Internacional, Corinthians drew 1-1 at Racing CM and Defensa y Justicia prevailed 1-0 at Cesar Vallejo...////...