Rodrigo opened the scoring for the hosts with a composed finish after 19 minutes following a great pass from strike-partner Simone Zaza before the Italian found the bottom corner with a powerful drive to double their lead.
Ruben Sobrino halved the deficit for Alaves when a slide-rule pass from Martin Aguirregabiria sent the forward free to slot home, but Victor Laguardia's own goal nine minutes after the restart restored Valencia's two-goal advantage to secure maximum points.
Deportivo La Coruna and Las Palmas played out a 1-1 draw that will do little to aid either team's battle to avoid relegation.
Levante's 2-1 victory over Eibar on Friday evening meant Las Palmas were seven points from safety before kick-off, with their opponents one point further adrift in 19th place. sbobet online 24
Las Palmas took the lead in the third minute through a brilliant Alen Halilovic goal. He gained possession on the halfway line before driving at the home defence and curling a shot into the bottom corner from the edge of the penalty area.
However, Raul Albentosa headed Depor level after 22 minutes and, despite Lucas Perez and Halilovic going close, neither team could snatch the much-needed three points. sbobet online 24[/color]