Image source, Getty ImagesImage caption, Anthony Belleau, who joined Northampton from Clermont last May, won 12 caps for France between 2017 and 2019
Anthony Belleau starts at fly-half as Northampton Saints make six changes for their Champions Cup last-16 tie against Castres at Franklin's Gardens on Friday.
The Frenchman replaces Fin Smith, who suffered a head injury in last week's thrilling Prem victory over Saracens at Tottenham Hotspur Stadium.
With Trevor Davison, who is unlikely to play again this season because of a knee injury, and Manny Iyogun both ruled out, Danilo Fischetti starts at loose-head prop and Luke Green retains his place as the tight-head.
Craig Wright takes over from Curtis Langdon as the starting hooker.
South African lock JJ van der Mescht brings his power to the pack, while Callum Chick comes in at number eight, with Henry Pollock switching to open-side flanker and Tom Pearson dropping to the bench.
England centre Fraser Dingwall teams up with in-form Tom Litchfield in the midfield, while George Furbank captains the Prem league leaders from full-back.
Phil Dowson's side won three of their four matches to finish second in their pool, while Castres won two and lost two to come third in their group.
Saints beat Castres in the pool stage and the quarter-finals during their run to the final last season.
Castres ended a three-match losing run by beating bottom-side Montauban last weekend to move into 10th place in the Top 14.
They are captained by flanker Baptiste Delaporte, while former All Black centre Jack Goodhue is one to watch in the backs.
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Northampton: Furbank (capt); Freeman, Litchfield, Dingwall, Ramm; Belleau, McParland; Fischetti, Wright, Green, Lockett, Van der Mescht, Kemeny, Pollock, Chick.
Replacements: Langdon, West, Kundiona, Prowse, Munga, Pearson, Weimann, Hutchinson.
Castres: Chabouni; Ambadiang, Botitu, Goodhue, Karawalevu; Herve, Fernandez; Walcker, Durand-Pradere, Corato, Ducat, Vanverberghe, Delaporte (capt), Ardron, Papalii.
Replacements: Colonna, Guerois-Galisson, Azar, Maravat, Cope, Ramototabua, Arata, Palis.
Television match official (TMO): Ben Whitehouse (Wales)
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