WATCH: Racing star gets a straight red for a headbutt

Racing 92 kept themselves in the hunt for a Champions Cup quarter-final place with a 29-7 win over Top 14 rivals Castres on Saturday.

Leone Nakarawa, Virimi Vakatawa, Dimitri Szarzewski and Louis Dupichot all went over for Racing, while Maxime Machenaud added a penalty and two conversions, and Teddy Iribaren one conversion.