Saints head to the Stade Ernest Wallon in Toulouse, where Pool Four rivals Castres await them.
While Castres have had a week to recover and prepare after being beaten by Ulster last Friday, Saints were in European action against Glasgow last Sunday.
"The tournament scheduling has not been particularly kind to us in the first two rounds," Northampton rugby director Jim Mallinder said.
"And having just five days to prepare for a tough match is certainly not ideal.
"However, we are going to France in good spirits after showing our character last Sunday to fight back and secure a bonus-point win, and we will be doing everything we can to get the positive result we want."
Northampton have played Castres in their last two European campaigns, winning three out of four fixtures. The solitary defeat, though, was an emphatic one - 41-22 in France last December.
"Having played Castres in both of our last two Heineken Cup campaigns, we have an idea of what to expect - some big runners, strong set-piece work and accurate goalkicking," Mallinder added.
"We also know how difficult Castres are to play at home.
"They have not lost in front of their own fans this season, and even though the game is in Toulouse they will still be very difficult to beat."
Northampton are without injured full-back James Wilson, so Stephen Myler switches positions and Ryan Lamb starts at fly-half in a team otherwise unchanged from the one that defeated Glasgow 24-15.
Glasgow face a crucial encounter at home to Ulster tomorrow, knowing they must beat last season's tournament runners-up to realistically keep alive their quarter-final hopes.
"We were pleased with how we performed in the first 30 minutes at Northampton," Glasgow head coach Gregor Townsend said.
"But we are well aware that against the calibre of opponents we play in this competition we need to be at the top of our game for the full 80.
"Our 18-10 defeat to Ulster on the first night of the RaboDirect PRO12 season was quite similar to the Northampton game in that we did a lot of things very well but didn't quite sustain it."
Glasgow will be without wing Sean Lamont, who suffered a facial injury against Saints, so Alex Dunbar lines up in the number 11 shirt, while two changes up-front see starts for lock Tom Ryder and flanker Chris Fusaro.
Ulster field their influential South African half-back Ruan Pienaar for his first start since completing Test duties in the Rugby Championship, with back-row forward Nick Williams also returning.
But star flanker Stephen Ferris has not recovered in time from a back injury, so young prospect Iain Henderson continues following an impressive display during last week's bonus point win against Castres.
"Glasgow are a formidable team, particularly at home," Ulster head coach Mark Anscombe said.
"We have to play for the full 80 minutes against them if we are to come away with the win. We can't afford to put in a performance for 50 or 60 minutes, like we have done in previous weeks."
Gilbert has released a new line of rugby cleats. The Gilbert Virtuo 8S is part of the exciting new product. Check it out.
The entire All Blacks apparel line has been updated for 2013/14. Check out the New Zealand All Blacks polo.
The Nike Tiempo is a solid rugby cleat and one of few styles still made from full-grain natural leather.
The Gilbert Blitz 8S rugby cleat is a great cleat at a great price of $69.99. Get a new pair of cleats today.
A cool looking all black rugby cleat with the high performance adidas is known for. Get in the Gear!
Wear the crest of the British and Irish Lions on your t-shirt. A great look for the summer.
The All Blacks Performance t-shirt is black with hints of blue from the training jersey. Very Cool.
The New Zealand All Blacks training jersey for 2013/14. Get in the Gear!
The USA Rugby Pro Alternate rugby jersey is perfect for any fan of the Eagles. Get yours to wear during the summer Test matches.
The NEW All Blacks 2013/14 jersey has arrived at World Rugby Shop. Dare to wear the colors of the All Blacks.