Northampton: Ramm; Freeman, Litchfield, Dingwall (capt), Sleightholme; Smith, Mitchell; Iyogun, Langdon, Millar-Mills, Mayanavanua, Lockett, Scott-Young, Pollock, Augustus.

Replacements: Wright, West, Green, Munga, Coles, Mapu, McParland, Hutchinson.

Castres: Chabouni, Raisuqe, Seguret, Dupont, Hulleu; Le Brun, Arata (capt), Guerois-Galisson, Zarantonello, Azar, Ducat, Nakarawa, Peysson, Ardron, Tukino

Replacements: Colonna, De Benedittis, Corato, Babillot, Papalii, Fernandez, Botitu, Baget.

Referee: Sam Grove-White (Sco)