In all, there are six changes in the squad from that which lost 3-0 to Munster in the Celtic League at the weekend, in addition to a series of positional changes to the starting fifteen as Connacht bod to reach the quarter-finals of the competition for the second year in succession.
Connacht expect a tough challenge from the French side in the first leg tie which takes place at the Sportsground on Saturday (kick-off 2pm), with the second leg in the south of France the following Saturday.
Scrum-half Mike Walls and outside centre Darren Yapp are the only two to start in the same positions in the backline. Wayne Munn comes into the side on the left-wing, with David Hewitt starting at fly-half. Positional changes see Conor McPhillips swapping wings, Matt Mostyn going to full-back and Mark McHugh going to inside centre.
Up front, Mike McCarthy comes back into the side to partner Andrew Farley in the second row, while Tom Carter returns at openside flanker, with prop Warren O'Kelly and back rower Mick Carroll being added to the replacements bench.
Connacht coach Michael Bradley knows that his side will have their work cut out if they are to advance to a quarter-final showdown against either London Irish or Narbonne at the expense of the former French champions, having overcome another French side Beziers in the last round.
"We expect Pau to be somewhat similar to Beziers but perhaps even more of a threat behind the scrum they have shown this season they have the ability to run in some nice tries," said Bradley.
"They are probably a more balanced side than Beziers and it is going to be an unbelievably tough tie but we have to focus on this home leg and then make any assessment on what we may be required to do in the away game.
"We would have preferred to play away in the first leg as now there is a bit of pressure on us to get a result and, hopefully, a decent margin of points difference to take into the second leg," he said.
Pau, winners of this competition four years ago and former Heineken Cup semi-finalists, come into this encounter with a rich vein of form.
They defeated Agen on Saturday to maintain a 100% home record this season and five days earlier scored a 292-9 draw away to leaders Brive who had won all five games up to then in the French championship.
Pau, who scored home and away wins over Parma in the last round, have a very settled side all season built around current French No.8 Imanol Harinordoquy, and current French centre Damien Traille, former Australian lock Garrick Morgan, and a strong half-back partnership of former French internationals Philippe Carbonneau and David Aucagne.
As usual, children will be admitted free to the Sportsground on Saturday and Connacht fans are being urged to come out in force and help the side achieve a good result to take to France the following week.
Connacht : M. Mostyn; C. McPhillips, D. Yapp, M. McHugh, W. Munn; D. Hewitt, M. Walls; D. McFarland, B. Jackman, A. Clarke; M. McCarthy, A. Farley; M. Swift, T. Carter, J. O'Sullivan.
Replacements: J. Fogarty, W. OÂ¹Kelly, M. Lacey, M. Carroll, C. OÂ¹Loughlin, E. Elwood, T. Robinson.