South African scrum-half Rory Kockott has been handed a starting jersey for Castres in their Heineken Cup clash with Northampton Saints on Friday.
Kockott has been in the headlines recently after publicly stating his desire to leave the club in order to pursue Test rugby with France or SA.
The French outfit visit Franklin's Gardens on Friday sitting two points ahead of the Saints in Pool 4, meaning that a victory is essential for the home team to continue their European journey.
But the Saints are in contention thanks to an against-the-odds win over pool leaders Ulster in December, and boss Mallinder says that the atmosphere in the camp this week has been similar to the days before the trip to Ravenhill.
"We still have a massive point to prove in Europe, and the players know what is expected of them on Friday night," he told the Northampton website.
"We need a win to keep our destiny in our own hands, especially as Castres are two points ahead of us in the pool.
"We also know that it will not be easy against one of the top teams in France. Castres have been in superb form over the past few months and have been playing a style of rugby which makes the most of their big forwards and speed out wide.
"It is a massive challenge for us, and all of the focus has been on what we need to do on Friday. We are just about playing knockout rugby, so getting the win is all that matters.
"But we've been playing well recently, scoring good tries and defending well, so there is plenty for us to build on and we are in a positive frame of mind to get our home form back."
Northampton name James Wilson in place of Ken Pisi, who is ruled out due to an ankle injury. Stephen Myler continues at fly-half ahead of Ryan Lamb while England squad members Calum Clark and Tom Wood join now Saxon Phil Dowson in the back-row.
Northampton: 15 Ben Foden, 14 James Wilson, 13 George Pisi, 12 Dom Waldouck, 11 Jamie Elliott, 10 Stephen Myler, 9 Lee Dickson, 8 Phil Dowson, 7 Tom Wood, 6 Calum Clark, 5 Courtney Lawes, 4 Samu Manoa, 3 Paul Doran-Jones, 2 Dylan Hartley (capt), 1 Soane Tonga'uiha.
Replacements: 16 Mike Haywood, 17 Alex Waller, 18 Tom Mercey, 19 Mark Sorenson, 20 GJ Van Velze, 21 Martin Roberts, 22 Ryan Lamb, 23 Tom May.
Castres: 15 Brice Dulin, 14 Max Evans, 13 Romain Cabannes, 12 RÃ©mi Lamerat, 11 Marcel Garvey, 10 Daniel Kirkpatrick, 9 Rory Kockott, 8 Antonie Claassen, 7 Yannick Caballero, 6 Jannie Bornman, 5 Iosefa Tekori, 4 Christophe Samson, 3 Anton Peikrishvili, 2 Mathieu Bonello, 1 Yannick Forestier.
Replacements: 16 Brice Mach, 17 Saimone Taumoepeau, 18 MichaÃ«l Coetzee, 19 Matthias Rolland, 20 Paul Bonnefond, 21 Pedrie Wannenburg, 22 Pierre Bernard, 23 Thomas Sanchou.
Date: Friday, January 11
Venue: Franklin's Gardens
Referee: George Clancy (Ireland)
Assistant referees: Paul Haycock (Ireland), Michael Black (Ireland)
Television match official: Peter Ferguson (Ireland)
Timekeeper: Matthew Peters (England)
Citing commissioner: Douglas Hunter (Scotland)
Assessor: Fergus Neil (Scotland)