Although the France striker failed to find the net, he played a pivotal role in securing victory for Ancelotti's men, setting up Cristiano Ronaldo for his 10th goal in five league games this season.
Benzema's performance did not go unnoticed by his coach, who was quick to praise the 26-year-old after the game.
AS quote the Italian as telling reporters: "The key to the game was the second goal and Karim had an important evening, creating the goal for Cristiano.
"His work had a lot of merit even if he didn't score. Sometimes it's better to pass.
"It’s great that we won a difficult game against a team that played well, but we controlled the game.
"We suffered when we had to suffer and played when we had to play. The performance was good. We had a good attitude and deserved to win."
That backing will come as a substantial boost to Benzema, who had previously come in for criticism due to his lack of goals.
Goalkeeper Iker Casillas, who has also seen his form come under the microscope, kept a clean sheet on his return to the side, with Keylor Navas having been preferred for Real's midweek win over Elche.
Ancelotti added: "Casillas had a very good game, like everyone else.
"We kept a clean sheet for the second time in the league and that's good."
