Saracens have one foot in the last eight of the European Challenge Cup after beating Bayonne 36-0 in a fiery game that saw five yellow cards.
Gordon Ross kicked Saracens into a 12-0 lead before Neil de Kock sent Kameli Ratuvou over for the opening try on 30 minutes.
However, the half ended with Nicolas Laffite, Census Johnston and Julian Fiorini all in the sin-bin in a bad-tempered clash.
De Kock, Noah Cato and Chris Jack all scored in the second half to clinch a bonus point before Hugh Vyvyan and Anthony Etchegaray were sin-binned for fighting.