Inter edge Genoa to go top
Barca finished the season second in the standings on 82 points, four behind champions Real Madrid who visit Leganes later on Sunday. Alaves are 16th on 39.
Former Real youth player Joselu pulled a goal back for Alaves in the 59th minute, powering in a header from a free kick, but Benzema rounded off the victory for second-placed Real with an exquisite solo run and goal in the 70th minute.
Champions Barcelona moved five points clear at the top of La Liga with a 2-1 win at Getafe, while Real Madrid fell to a 2-0 defeat by Real Sociedad.
