Four first-half goals set Barca on their way to the three points at the Camp Nou in what was new coach Tito Vilanova's first competitive match in charge.
"We have started very well and in the league it is always important to start well," Alves told Barca TV. "Our team was very organised from the first minute.
"Last year we had many accidents, and we weren't competitive enough in the league. Tonight was an important moment and will boost the team's morale."
Perennial rivals Real Madrid got off to a shaky start in their defence of the La Liga crown as they drew 1-1 at home to Valencia.