Gloucester kept their faint hopes of making the Heineken Cup last eight just about alive after recording a 23-8 win over Biarritz on Saturday.
BO did however secure a quarter-final place thanks to the Cherry and Whites failing to pick up a four-try bonus point.
The French team cannot be caught in Pool Two but Gloucester have kept themselves in the best runner-up contest.
At the very least they should have a place in the Amlin Challenge Cup which goes to three of the second-placed pool teams.
Biarritz were without eight players from the side which thumped Gloucester 42-15 at Parc des Sports, Aguilera, in October.
Those included influential Test stars Fabien Barcella, Dimitri Yachvili and Damien Traille, all of whom suffered left knee injuries against Stade Francais last week.
Gloucester's were pinning their hopes of quarter-final qualification by securing a best runners-up place.
The home side came out of the blocks the better and, at half-time, were leading 13-3. The score, though, did not reflect how much of the game Gloucester controlled.
Biarritz hardly made an inroad into the home 22 and their only points came from a long-range penalty from fly-half Valentin Courrent.
Gloucester's pack out-muscled the Frenchmen and only a few wrong options denied them an even bigger lead at the interval.
Centre Tim Molenaar dropped a pass from ex-England wing Lesley Vainikolo within five metres of the line early on before fly-half Nicky Robinson landed the first of his two penalties during the period.
Biarritz's line was finally breached on 20 minutes when loose-head prop Alasdair Dickinson raced away from an attacking ruck near the 22 metre line and found the dashing Vainikolo on hand to take the scoring pass.
Robinson landed the conversion and popped over an easy 20 metre penalty when Biarritz illegally slowed a ruck down to give the English side the platform to work from in the remaining 40 minutes.
Biarritz provided a few moments resistance after the break but the initiative soon swung back towards the home side.
However, needing another three tries for a bonus point, captain Gareth Delve opted for Robinson's kicking instead.
And bizarrely, just before the hour and with Biarritz on the rack when former England back row Luke Narraway knocked-on as the ball squirted out of a defending scrum five, Robinson was handed the ball and, subsequently, sent an easy kick wide of the posts.
But another charging run from centre Eliota Fuimaono-Sapolu, rightly awarded the man of the match award, set-up Vainikolo to feed Molenaar for a second and secure the victory.
Biarritz rallied towards the end and international number eight Imanol Harinordoquy grabbed a pick-up and go try from a ruck near the home posts but it was just a consolation and did nothing to dent the home joy.
Tries: Vainikolo, Molenaar
Con: Robinson 2
Pen: Robinson 3
Gloucester:15 Olly Morgan, 14 James Simpson-Daniel, 13 Tim Molenaar, 12 Eliota Fuimaono-Sapolu, 11 Lesley Vainkolo, 10 Nicky Robinson, 9 Rory Lawson, 8 Gareth Delve (c), 7 Akapusi Qera, 6 Alasdair Strokosch, 5 Alex Brown, 4 Dave Attwood, 3 Greg Somerville, 2 Scott Lawson, 1 Alasdair Dickinson.
Replacements: 16 Darren Dawidiuk, 17 Nick Wood, 18 Pierre Capdevielle, 19 Adam Eustace, 20 Luke Narraway, 21 Dave Lewis, 22 Freddie Burns, 23 Tom Voyce.
Biarritz Olympique: 15 Paul Couet-Lannes, 14 Takudzwa Ngwenya, 13 Arnaud Mignardi, 12 Ayoola Erinle, 11 Ilikena Bolakoro, 10 Valentin Courrent, 9 Yann Lesgourgues, 8 Imanol Harinordoquy, 7 Samiu Vahafolau, 6 Magnus Lund, 5 Manuel Carizza, 4 JÃ©rÃ´me Thion, 3 RÃ©my Hugues, 2 Romain Terrain, 1 Eduard Coetzee.
Replacements: 16 Benoit August, 17 Yvan Watremez, 18 Mosese Moala, 19 Trevor Hall, 20 Fabien Alexandre, 21 Benoit Guyot, 22 Laurent Tranier, 23 Nicolas Brusque,
Referee: George Clancy