Riaan Swanepoel scored a vital try to lift Brive out of the relegation zone with a 27-0 win over Stade Français in the Top 14.
Needing a bonus-point victory to avoid relegation, Brive produced a sterling home performance to blank out Stade, with Swanepoel crossing in the 64th minute for the sought-after fourth try.
The result meant Bayonne, despite their 45-12 thrashing of La Rochelle, have been relegated to the Pro D2 league, together with Lyon.
Elsewhere, Toulon crushed Oyonnax 46-17 to cement their place at the top of the table and Clermont beat Montpellier 29-17 to secure second spot.
Toulouse edged Bordeaux-Begles 23-22 and will host Oyonnax in the first play-off qualifier next week, while Racing Métro’s 53-10 defeat of Castres will see them play the second play-off match against neighbours Stade in a Parisian derby. The winners of the two matches will advance to the semi-finals where Toulon and Clermont await.
In the only other match, hooker Deon Fourie scored one of two tries as Lyon upset Grenoble 29-24.
Round 26 results:
Brive 27 Stade Français 0
Bayonne 45 La Rochelle 12
Toulon 46 Oyonnax 17
Montpellier 17 Clermont 29
Toulouse 23 Bordeaux-Bègles 22
Racing Métro 53 Castres 10
Lyon 29 Grenoble 24
Photo: Diarmid Courreges/AFP Photo