There are also a number of positional switches in a rejigged team, with the most notable seeing Fionn Carr move to the full-back position.
Head coach Eric Elwood hopes the switches will give his side the spark needed to reignite Connacht's season - they have suffered seven defeats in-a-row.
There are two changes in the pack with Bernie Upton replacing Michael Swift in the second row and Mike McComish returning at number 8.
Young centre Eoin Griffin is the only player to retain his place in a freshened up back-line. Like winger Shane Monahan, Griffin will be making his European debut.
Monahan and Brian Tuohy fill the wing berths and link up with Fionn Carr, who gets a chance to impress at full-back in a new-look back-three.
Niva Ta'auso returns to the Connacht midfield, with Ian Keatley and Frank Murphy resuming their half-back partnership.
Experienced forward Mike McCarthy will earn his 100th cap for Connacht this weekend. The 29-year-old joined Connacht in 2003 before having spells with London Wasps and Newcastle Falcons. Since returning to the Sportsground in 2007, he has been a regular in the Connacht team.
Commenting on his side's recent form and Saturday's encounter, Elwood said: "We are competitive and doing a lot a good things, we have to keep believing and persevere.
"We're sending out our strongest team possible in the hope of getting that elusive win. They are working hard for it and deserve to get the win they are looking for. If it is this week, great, if it is next week so be it.
"This game itself has a little bit of history. We beat Bayonne here (16-13), they were a little cross with that defeat and indicated they are determined to get some payback."
CONNACHT (v Bayonne): Fionn Carr; Shane Monahan, Eoin Griffin, Niva Ta'auso, Brian Tuohy; Ian Keatley, Frank Murphy;Brett Wilkinson, Sean Cronin, Jamie Hagan, Bernie Upton, Mike McCarthy, Andrew Browne, Johnny O'Connor, Mike McComish.
Replacements: Adrian Flavin, Rodney Ah You, Ronan Loughney, Michael Swift, Shane Conneely, Cillian Willis, Miah Nikora, Keith Matthews.