Close rivals Montpellier and Racing Métro 92 will clash in the Top 14 on Friday night in the battle for 5th place.
Both sides come into Round 21 tied on 54 points, with 12 wins and eight losses each as they battle to remain inside the crucial playoff spots.
Given that Perpignan remain just three points behind both sides, neither team can afford to drop crucial points.
Montpellier come into Friday's match on the back of a bonus-point defeat away to Castres last weekend, where all of their points came in the first half including tries from Yoan Artru and Agustin Creevy.
Racing on the other hand were comfortable winners over Grenoble in Paris, earning revenge for their defeat earlier in the season. Argentinian international winger Juan Imhoff crosses twice in the comfortable 23-3 win, with Jonathan Wisniewski scoring the remaining points.
The Parisian big-spenders have already recruited Ireland fly-half Jonathan Sexton for next season, with other international stars including Jamie Roberts, Dan Lydiate, Brian Mujati and more also linked.
A second-half try from replacement Alexandre Bias ultimately proved to be the match-winner when these two teams last met this season back in Week 9, as Montpellier snatched a 16-12 win thanks to the boot of Benoit Paillaugue, with Racing's points solely coming from their scrum-half Maxime Machenaud.
With so little to separate both sides coming into Friday's meeting in Montpellier, the outcome is difficult to call.
"Friday is another huge game for us. We fear Racing - it would be pretentious not to fear a team that has won their last seven matches," said Paillaugue, who will play at fly-half on Friday with Julien Tomas at scrum-half.
"In the Top 14, anyone can defeat anyone. We would love to stay undefeated at home, and we will work hard to be ready for Friday."
Montpellier: 15 Lucas Gonzales Amorosino, 14 Timoci Nagusa, 13 Thomas Combezou, 12 Paul Bosch, 11 Yohann Artru, 10 Benoit Paillaugue, 9 Julien Tomas, 8 Alex Tulou, 7 Alexandre Bias, 6 Fulgence Ouedraogo, 5 Thibaut Privat, 4 Alikisio Fakate, 3 Maximiliano Bustos, 2 Agustin Creevy, 1 Yvan Watremez
Replacements: 16 Charles Geli, 17 Nahuel Lobo, 18 Hendrikus Hancke, 19 Kelian Galletier, 20 Hamish Gard, 21 Matthew Carraro, 22 Martin Bustos Moyano, 23 Barry Faamausili
Racing Metro: 15 Juan Martin Hernandez, 14 Benjamin Fall, 13 Henry Chavancy, 12 Fabrice Estebanez, 11 Juan Imhoff, 10 Olly Barkley, 9 Sebastien Descons, 8 Masinivanua Matadigo, 7 Bernard Le Roux, 6 Alvaro Galindo, 5 Francois Van der Merwe, 4 Karim Ghezal, 3 Its Salemane, 2 Thomas Bianchin, 1 Julien Brugnaut.
Replacements: 16 Benjamin Noirot, 17 Eddy Ben Arous, 18 Fabrice Metz, 19 Jacques Cronje, 20 Virimi Vakatawa, 21 Jonathan Wisniewski, 22 Camille Gerondeau, 23 Juan Pablo Orlandi.
Previous result Montpellier won 16-12
Date: Friday, March 8
Venue:Stade Yves du Manoir
Kick-off: 20.50 (19.50 GMT)
Referee: Mathieu Raynal