Paris - Former champions Toulon failed to score a point for the first time in more than five years as they were crushed 39-0 by Toulouse on Sunday.
Patrice Collazo's side conceded five tries in what was a new low for an outfit who have lifted the French title and the European Cup twice since losing 23-0 to Stade Francais in November 2013.
They sit in tenth place in the table with only five league wins so far and are at risk of missing out on qualification for next year's Champions Cup.
Flyhalf Anthony Belleau said there were only negatives to take from the humiliation.
"It's not just the score that's disappointing it's the content. We only made it into their 22m once. There's nothing good from tonight," the 22-year-old France international said.
"We were given a lesson tonight. Taking a thrashing like that, not scoring a single point, it's difficult to accept but we have to move on so we can focus on the next part of the season."
In an ill-tempered opening 20 minutes, where two separate scuffles broke out, Thomas Ramos claimed a 6-0 lead for the hosts.
France winger Yoann Huget dived over for his sixth try of the season after half an hour and Ramos added the two points for a 13-0 half-time advantage.
Springboks wing Cheslin Kolbe as well as France scrumhalf Antoine Dupont were among the second-half try scorers while Wales halfback Rhys Webb and winger Daniel Ikpefan were shown yellow cards for the visitors.
The win extends Toulouse unbeaten run to 11 games across all competitions and leaves them three points behind leaders Clermont.
Bordeaux-Begles produced a storming performance to thrash Racing 92 40-7 as the home side pounced on Ole Avei's early red card to run in tries through George Tilsley, Nans Ducuing and Yann Lesgourgues.
A late penalty try appeared to have denied Bordeaux the bonus point but Ducuing's second try in the last action of the match secured it and lifted Bordeaux to fourth in the table at the halfway point of the competition, leapfrogging Racing who drop to sixth.
A Racing penalty try five minutes from time which resulted in a yellow card for Cameron Woki meant Bordeaux needed to score for the extra point. With Racing prop Census Johnston sent to the sin-bin 12 seconds before the 80 minutes was up, Bordeaux had one last chance.
The penalty was kicked into touch and from the line-out they sprayed the ball wide with former All Black Seta Tamanivalu, playing his first game for Bordeaux, feeding France winger Ducuing for the run-in.
Elsewhere, Fijian wingers Timoci Nagusa and Nemani Nadolo both muscled through for tries as Montpellier snapped a two-game losing streak with a 41-13 win over Pau.
South African flanker Jacques du Plessis produced a second half double and Paul Willemse also touched down while scrum-half Benoit Paillaugue added 14 points from the boot as Montpellier recorded only their second win in six league games.
Vern Cotter's side picked up an offensive bonus point which lifts them to eighth place, four points behind Stade Francais in the last of the play-off positions.
Pressure is now building on Pau coach Simon Mannix whose side have now lost six in a row and stay third from bottom.