Faloon was ruled out of selection earlier this week due to a fractured eye socket he incurred during the sides' first meeting at the Sportsground last Friday night.
Dan Parks will lead his side out once again - with Gavin Duffy and John Muldoon among the walking wounded - as Connacht look for an historic double over the French giants.
Out-half Parks is the Heineken Cup's leading points scorer so far this season with 48 points, bringing his all-time total to 403 points.
The former Scotland international is two points short of reaching the half-century mark in the Heineken Cup for the fifth time in eight seasons.
Meanwhile, teenager Robbie Henshaw, who this week signed a full two-year contract with Connacht, will line out at full-back.
On the bench, forwards Nathan White (calf) and George Naoupu (foot) make a welcome return to the squad having both missed out on last weekend's round 3 clash.
Commenting on the return fixture with Biarritz, assistant coach Dan McFarland said: "There was a very calm approach to last Friday's game. Yes, it was a big occasion for the province but as a squad we just concentrated on the fact that we needed to win if we were to keep our hopes of qualifying for the quarter-finals alive.
"We were thrilled to win but we can't be happy with just that alone, the task now will be to go to Biarritz and back it up.
"It is great to see these young players coming through and delivering at Heineken Cup level. The key now is to move away from producing one huge performance and do it consistently and that starts in Biarritz on Friday."
CONNACHT (v Biarritz Olympique): Robbie Henshaw; Tiernan O'Halloran, Danie Poolman, David McSharry, Fetu'u Vainikolo; Dan Parks (capt), Kieran Marmion; Brett Wilkinson, Jason Harris-Wright, Ronan Loughney, Michael Kearney, Mike McCarthy, Andrew Browne, Johnny O'Connor, Eoin McKeon.
Replacements: Ethienne Reynecke, Denis Buckley, Nathan White, Daniel Qualter, George Naoupu, Paul O'Donohoe, Miah Nikora, Matthew Jarvis.