Castres booked themselves into a Top 14 semi-final against Toulouse after beating a poor Montpellier side 31-15 at Stade Ernest-Wallon on Friday.
There was only ever one side in it as CO, who were looking for revenge after going down to Montpol at this same stage last year, shot out of the blocks and took a stranglehold of the game.
Castres had an early lead when Pierre Bernard opened matters with two minutes gone. However, moments later they suffered a blow when scrum-half Thierry Lacrampe was sent to the sin-bin after he slapped down the ball at the base of a ruck. Montpellier did not take advantage of their extra man and, in fact, found themselves 6-0 down when Romain Teulet slotted on fifteen minutes.
Montpellier it seemed had stayed on the bus and when Joe Tekori was ruled not to have grounded in the midst of Lacrampe's return, there was serious pressure being applied from all areas.
But unfortunately for Fabien GalthiÃ© his side continued in their slumber and from the ensuing scrum, Lacrampe spotted Fulgence Ouedraogo shoot out to Barnard and duly scampered through the gap. Teulet's extras made it 13-0 with a quarter of the match gone.
Then a sudden and unexpected shift occurred at Stade Ernest Wallon as, from a charge-down of Mamuka Gorgodze, Montpol almost crossed. First the hefty Georgian gathered the loose ball and then offloaded to Francois Trinh-Duc, who was unfortunately for them hauled down five metres short before Castres offended. Martin Bustos Moyano made it 13-3.
Referee Patrick Pechambert gave off the impression he would not tolerate blatant offences and soon proved it when Mikael De Marco was binned for holding Lacrampe. Barnard made it 16-3 but then came the moment that gave Montpellier the shot in the arm they desperately needed as number eight Alex Tulou stayed strong to power over in the left-hand corner.
Teulet responded from the tee though following Bustos-Moyano's missed conversion from the touchline as the duo went in at half-time in Toulouse with Castres ahead by 19 to 8.
Montpellier needed the first score after the break but once again shot themselves in the foot as Barnard duly punished them from distance. He was at it again with 50 minutes gone to make the scoreline look almost unassailable at 25-8. Cue a treble change being made from Montpol as locks Thibaut Privat, De Marco and hooker Agustin Creevy left the field for Hendrikus Hancke, Alikisio Fakate and Erasmus Jansen van Vuuren respectively.
It was all or nothing from here on in for them.
What gave them a glimmer of hope was when Castres lock Tekori was shown red for a high tackle on Eric Escande. That led to Fakata crashing over for a converted try with eleven minutes to go. But when Teulet and then Barnard kicked from the tee, Castres' win was secured.
Pen: Barnard 5, Teulet 3
Tries: Tulou, Fakate
Castres: 15 Romain Teulet, 14 Romain Martial, 13 Max Evans, 12 Romain Cabannes, 11 Marc Andreu, 10 Pierre Bernard, 9 Thierry Lacrampe, 8 Matemini Masoe, 7 Yannick Caballero, 6 Ibrahim Diarra, 5 Joe Tekori, 4 Matthias Rolland, 3 Luc Ducalcon, 2 Mathieu Bonello, 1 Yannick Forestier.
Replacements: 16 Marc Antoine Rallier, 17 Saimone Taumoepeau, 18 Rodrigo Capo Ortega, 19 Steve Malonga, 20 Rory Kockott, 21 Seremaia Bai, 22 Thomas Sanchou, 23 Karena Wihongi.
Montpellier: 15 Lucas Gonzales Amorosino, 14 Timoci Nagusa, 13 Thomas Combezou, 12 Santiago Fernandez, 11 Martin Bustos Moyano, 10 Francois Trinh-Duc, 9 Eric Escande, 8 Alex Tulou, 7 Mamuka Gorgodze, 6 Fulgence Ouedraogo, 5 Thibaut Privat, 4 Mickael De Marco, 3 Giorge Jgenti, 2 Agustin Creevy, 1 Juan Figallo.
Replacements: 16 Erasmus Jansen van Vuuren, 17 Naama Leleimalefaga, 18 Hendrikus Hancke, 19 Alikisio Fakate, 20 Remy Martin, 21 Paul Bosch, 22 Pierre Berard, 23 Maximiliano Bustos.
Referee: Patrick Pechambert