Biarritz progressed to the Challenge Cup semi-finals after overcoming Gloucester 41-31 in an impressive showing at Kingsholm on Thursday.
Gloucester were beaten by a more streetwise rival, having competed in this type of knockout match so frequently over the past few seasons.
Indeed, the Cherry and Whites started the better of the two sides and were good value for an early lead after a decent try from centre Mike Tindall.
However, first half sin-binnings of Dario Chistolini and Koree Britton gave the visitors a weakness to exploit and they needed no second invitation.
First-half tries came from Teddy Thomas (2) and Arnaud Heguy while Dimitri Yachvili kicked over the points as Biarritz went in 27-14 to the good.
Chasing the game in the second half, Gloucester threw caution to the wind as they sought to keep their European hopes alive, but came up against a well organised defence in no mood to concede, and a side able to ruthlessly exploit any chance.
The killer blow came on 56 minutes. Trailing by ten points, Sione Kalamafoni powered close to the Biarritz line as Gloucester poured forward looking for a critical score.
However, possession was conceded and the French side countered upfield to score through outside centre Benoit Baby. It was now a seventeen point lead at Kingsholm.
Gloucester refused to throw in the towel and late scores from replacements Shane Monahan and Huia Edmonds allowed Gloucester to finish with some consolation.
Biarritz will face either London Wasps or Leinster in the semi-finals later this month.
Tries: Tindall, Monahan, Edmonds
Con: Burns 2
Pen: Burns 4
Yellow: Chistolini (17 mins), Britton (29 mins)
Tries: Thomas 2, Heguy, Baby, Burotu
Con: Yachvili 5
Yellow: Harinordoquy (77 mins)
Gloucester: 15 Martyn Thomas, 14 Charlie Sharples, 13 Henry Trinder, 12 Mike Tindall (c), 11 Jonny May, 10 Freddie Burns, 9 Dave Lewis, 8 Sione Kalamafoni, 7 Akapusi Qera, 6 Tom Savage, 5 Will James, 4 Lua Lokotui, 3 Shaun Knight, 2 Koree Britton, 1 Nick Wood.
Replacements: 16 Huia Edmonds, 17 Dan Murphy, 18 Dario Chistolini, 19 Andy Hazell, 20 Gareth Evans, 21 Dan Robson, 22 Billy Twelvetrees, 23 Shane Monahan.
Biarritz: 15 Marcelo Bosch, 14 Takudzwa Ngwenya, 13 Benoit Baby, 12 Damien Traille, 11 Teddy Thomas, 10 Jean-Pascal Barraque, 9 Dimitri Yachvili, 8 Imanol Harinordoquy, 7 Raphael Lakafia, 6 Tanguy Molcard, 5 Mathias Marie, 4 Erik Lund, 3 Gomez Kodela, 2 Arnaud Heguy, 1 Eugene Van Staden.
Replacements: 16 Benoit August, 17 Thomas Synaeghel, 18 Ben Broster, 19 Pelu Lan Taele, 20 Seremaia Burotu, 21 Yann Lesgourgues, 22 Charles Gimenez, 23 Paul Couet-Lannes.
Referee: John Lacey (Ireland)
Assistant referees: Dudley Phillips (Ireland), David Wilkinson (Ireland)