Bordeaux-Bègles produced a stunning comeback as they overcame an 11-point deficit to beat Toulon 28-23 at Stade Chaban Delmas.
After trailing 20-9, they ran in three tries, including a double for Metuisela Talebula to turn it around and keep themselves in contention for a play-off place.
Toulon dominated the first half, scoring two tries through Josua Tuisova and Maxime Mermoz.
However a mix-up between Delon Armitage and Sébastien Tillous-Borde allowed Hugh Chalmers to go over on the stroke of half-time and give Bordeaux some hope.
And the home side took that momentum into the second half, with Talebula running in two tries as the match was turned on its head.
Although they let the victory slip away, Toulon secured a losing bonus point that takes them temporarily top of the table.
Bordeaux made the better start at the scrum with Xavier Chiocci penalised twice in quick succession. Pierre Bernard was off-target with his first shot at goal, but made no mistake second time to open the scoring.
Having been dominated for most of the opening ten minutes, Toulon were able to level matters when Ole Avei failed to release the ball at a ruck, Nicolas Sánchez slotting the resulting penalty.
Out of nowhere Toulon scored the first try of the game thanks to the power of their young winger Tuisova.
Seemingly with no space on the left, he shrugged off the tackles of Talebula and then Ole Avei before sprinting away from Lionel Beauxis to dot down the first try. Sánchez converted to make it 10-3.
Bordeaux responded with three more points from Bernard, but Toulon were almost over again when Chiocci went clean through before feeding Juan Smith. He didn't have the legs to get over though and Talebula tackled before earning the penalty by contesting at the breakdown.
The home side almost had their first try a couple of minutes later when Blair Connor picked off a pass from Sánchez and sprinted the length of the field, but the referee was playing advantage for an infringement at a maul, so it came back for a penalty which the Argentine fly-half slotted to stretch the lead to 13-6.
While Toulon had started to take control, they were proving too indisciplined, and after a warning for a maul that had been stopped illegally, they finally lost Hernández to a yellow card when he slowed down a ball five metres from the Toulon line. Bernard slotted a third penalty of the afternoon to cut the deficit to four.
Despite being a man down, Toulon hit straight back, with Mermoz going clean through in midfield. He then fed Sébastien Tillous-Borde inside him who was stopped just short of the line. With Bordeaux stretched, Mermoz then dived over the top of a ruck to dot down despite suspicions of a knock-on in the ruck. The extras from Sánchez stretched the lead to 20-9, with the home side missing far too many tackles to compete with a side like Toulon.
The visitors had also turned things around in the scrum, but after another penalty at the set-piece, Sánchez was off-target for the first time of the afternoon.
However with Toulon seemingly in control, Bordeaux got a way back into the match on the stroke of half-time with a comedy score from Chalmers. The back rower tackled Delon Armitage, on his return from suspension, behind his line and when the former England full-back dropped the ball, Chalmers tapped the ball down for the try. Bernard's conversion made it 20-16 at the break.
Bordeaux could have cut the deficit to a single point when Connor was tackled without the ball early in the second half, but Bernard's effort from 45 metres out was short.
Still, the momentum was with the home side, and they took the lead with a try from Talebula after 46 minutes. It came when Tillous-Borde was charged down at a ruck. Bernard was quickest to it and the ball was spread to the Fijian who dived over acrobatically. Bernard's conversion was off-target but Bordeaux led 21-20.
Having scored 12 unanswered points, Bordeaux were on a roll. And another try from Talebula allowed them to stretch their lead a little further. This time Sofiane Guitoune collected a loose ball in midfield and spotted a gap that he sprinted straight through. Talebula was in support and collected the low pass to go over on the left. From the touchline Bernard converted to make it more than a one-score game.
There were still 25 minutes remaining but Toulon looked short of ideas, and it was Bordeaux who looked more likely to score again, with Talebula breaking through again on the hour only for Sánchez to get back to collect his chip over the last man.
With three minutes to go Toulon put together a series of phases which ended with an intentional knock-on from Chalmers, earning him ten minutes in the bin and allowing Sánchez to cut the deficit to five points.
And with a minute remaining, Bordeaux lost Bernard to a knee injury, which puts his participation in next week's Six Nations game against Wales in doubt, but his team were able to see out the win.
Tries: Chalmers, Talebula 2
Cons: Bernard 2
Pens: Bernard 2
Yellow Card: Chalmers
Tries: Tuisova, Mermoz
Cons: Sánchez 2
Pens: Sánchez 2
Yellow Card: Hernández
Bordeaux-Bègles: 15 Lionel Beauxis, 14 Sofiane Guitoune, 13 Metuisela Talebula, 12 Thibaut Lacroix, 11 Blair Connor, 10 Pierre Bernard, 9 Heini Adams, 8 Peter Saili, 7 Hugh Chalmers, 6 Louis-Benoit Madaule (c), 5 Berend Botha, 4 Jandre Marais, 3 Jean-Baptiste Poux, 2 Ole Avei, 1 Jefferson Poirot
Replacements: 16 Beñat Auzqui, 17 Sébastien Taofifenua, 18 Julien Ledevedec, 19 Matthew Clarkin, 20 Yann Lesgourgues, 21 Baptiste Serin, 22 Charles Brousse, 23 Francisco Gomez Kodela
Toulon: 15 Delon Armitage, 14 Drew Mitchell, 13 Maxime Mermoz, 12 Juan Martín Hernández, 11 Josua Tuisova, 10 Nicolas Sánchez, 9 Sébastien Tillous-Borde, 8 Steffon Armitage, 7 Juan Martín Fernández-Lobbe, 6 Juan Smith, 5 Ali Williams, 4 Bakkies Botha, 3 Carl Hayman (c), 2 Jean-Charles Orioli, 1 Xavier Chiocci
Replacements: 16 Matias Cortese, 17 Florian Fresia, 18 Jocelino Suta, 19 Chris Masoe, 20 Mathieu Bastareaud, 21 David Smith, 22 Eric Escande, 23 Levan Chilachava
Referee: Alexandre Ruiz
Venue: Stade Chaban Delmas