John Ulugia's second-half try helped Clermont fight back to beat Bordeaux-Bègles 31-23 and move to the top of the Top 14.
Despite the absence of a number of regulars, Bordeaux looked set to complete the double over Clermont when Jayden Spence's try in the first half allowed them to open up an eight-point lead with just over half an hour to go.
However Clermont, who had conceded 51 points at Bordeaux, finished much the stronger, eventually denying their visitors even losing bonus point, while leapfrogging Toulon at the top.
Clermont were without 13 players coming into the game, seven international absences combined with another six injured players. However Bordeaux-Bègles had problems of their own on the injury front, while the likes of Louis-Benoit Madaule were given the weekend off after a lot of game time in recent weeks.
That meant the likes of Spence, Ulrich Beyers and Baptiste Serin were all in the run-on team, the former two making their first starts for their new clubs.
While Clermont looked the more dangerous team in the opening stages, it was a battle of the boots early on, with Mike Delany and Lionel Beauxis cancelling each other out with three penalties apiece.
Bordeaux threatened with ball in hand, notably from one counter-attack by Beauxis, but after the ball had made it way to Blair Connor, Ludovic Radosavljevic cynically killed the ball, and was fortunate to concede just a penalty. Beauxis found the target to put the visitors back in front.
On his debut Spence grabbed the first try just after the half-hour after a howler from Nick Abendanon. Having stolen a Clermont lineout on the right, Bordeaux spread the ball the other way. Out wide Metuisela Talebula tried to chip through and the Clermont full-back failed to gather before slipping, with Spence following up to collect the ball and dive over. Beauxis couldn't convert from the touchline but Bordeaux led 17-9.
The momentum was clearly with the visitors, but just before half-time Clermont got back on the attack. Delany was caught a little high by Berend Botha, and the South African was sin-binned, allowing the Kiwi fly-half to reduce the deficit to five points, with an extra man for the next ten minutes.
That was how it remained until the break, and despite being a man down, it was Bordeaux who struck first in the second half, again countering after Clermont had lost the ball in midfield. While Clermont slowed the attack, Beauxis dropped back into the pocket before slotting a drop goal to stretch the lead back to 20-12.
Clermont tried to respond, only for a scrum penalty to give Bordeaux respite in their own 22, and they missed the chance to extend their lead when Beauxis was off-target from the right when the home side were penalised in a maul.
Les Jaunards needed a response, and it came from a great run by Fritz Lee, who carried the ball out of his 22 and almost up to halfway, to get Clermont back on the front foot. Eventually Bordeaux were caught offside, allowing Delany to knock over his fifth penalty and bring Clermont back to within a score.
Back up to a full complement, Bordeaux hit back, with Beyers hammering a monster 55m penalty, which had plenty of room to spare. Again Clermont responded, with a huge Nalaga break leading to an offside from the visitors and an easy three points for replacement fly-half Brock James, who made a big impact after coming on for Delany.
On the hour Clermont finally got back in front, after a long period of possession, with Ulugia eventually the man to cross. While there seemed to be a clear knock-on in the build-up, Clermont kept coming, and eventually Ulugia slipped through two tackles, before having far too much power for Beauxis a couple of metres out. James' conversion made it 25-23 to the home side.
Thomas Domingo was very involved for Clermont, and after another charge from him, Bordeaux strayed offside, allowing James to add three more points, with the visitors seemingly fading.
Bordeaux, to their credit, kept trying things, but it was after one such counter from their own 22 that Matthew Clarkin was isolated, and James again made no mistake, pushing the lead out to eight points.
Beyers had the chance to get Bordeaux back within range of a bonus point, but his effort five minutes from time was off-target, despite being easier than his first penalty.
They didn't get another chance, and return home empty-handed and facing an uphill battle to make the top six.
Clermont are now more than ever in prime position to finish in the top two and secure a semi-final spot.
Pens: Delany 5, James 3
Pens: Beauxis 4, Beyers
Drop Goal: Beauxis
Yellow Card: Botha
Clermont: 15 Nick Abendanon, 14 Zac Guildford, 13 Aurélien Rougerie, 12 Benson Stanley, 11 Napolioni Nalaga, 10 Mike Delany, 9 Ludovic Radosavljevic, 8 Fritz Lee, 7 Alexandre Lapandry, 6 Julien Bonnaire (c), 5 Julien Pierre, 4 Jamie Cudmore, 3 Clément Ric, 2 John Ulugia, 1 Thomas Domingo
Replacements: 16 Ti'i Paulo, 17 Etienne Falgoux, 18 Sébastien Vahaamahina, 19 Peceli Yato, 20 Thierry Lacrampe, 21 Brock James, 22 Jean-Marcellin Buttin, 23 Daniel Kotze
Bordeaux-Bègles: 15 Ulrich Beyers, 14 Metuisela Talebula, 13 Jayden Spence, 12 Thibault Lacroix, 11 Blair Connor, 10 Lionel Beauxis, 9 Baptiste Serin, 8 Peter Saili, 7 Hugh Chalmers, 6 Matthew Clarkin (c), 5 Berend Botha, 4 Julien Ledevedec, 3 Francisco Gomez Kodela, 2 Beñat Auzqui, 1 Laurent Delboulbès
Replacements: 16 Ole Avei, 17 Jefferson Poirot, 18 Benjamin Venter, 19 Bertrand Guiry, 20 Yann Lesgourgues, 21 Pierre Bernard, 22 Charles Brousse, 23 Albert Toetu
Venue: Stade Marcel Michelin, Clermont-Ferrand
Referee: Sami Attalah