Real are three points clear of Barca.
Benzema told AS: "Sporting comes first. It will be a tough game because they are in need of points.
"We don't want to dwell on the Barcelona game and talk about them.
"We know they are one of the best teams in the world but I will tell you one thing: we are ready for the challenge."
"I am ready to play but we have a large squad and there are many players here who could be called upon to play Barca," he said.
"I will work hard, I have the coach's trust and I am happy to have played the last three games."