La Rochelle held off a stirring Toulouse fightback to storm back to the French Top 14 summit with a 27-21 win on Sunday.
Having already earned impressive wins at Toulon and Castres this season, unfancied La Rochelle claimed a third major scalp on their travels.
And a brave stand on their own tryline at the end of the game also denied four-time European champions Toulouse even the losing bonus point.
"Let's say we're in a dream and we'll try to wake up as late as possible," said backrower Romain Sazy, who insisted the players "never talk about" the possibility of winning the title.
Tries from Jone Qovu and Pierre Aguillon set La Rochelle on the way to victory while Australian fly-halves Zack Holmes and Brock James kicked the rest of the visitors' points.
"It's incredible what we're doing this year, we know that," said hooker Jeremie Maurouard.
Joe Tekori and Julien Marchand crossed for Toulouse but the defeat left them in eighth and four points off the top six play-off places.
Holmes gave La Rochelle an early lead from the tee in a brutal first half.
At one point, rampaging Fijian centre Levani Botia pole-axed Toulouse's Alexis Palisson.
The wing was so groggy from the challenge that when he stood up and tried to continue running, he stumbled uncontrollably into the touch judge.
Holmes added three more penalties before being forced off injured to be replaced by compatriot James.
Sebastien Bezy, meanwhile, had kicked two penalties for the hosts, who trailed 12-6 at the break.
Toulouse showed more purpose at the start of the second half and Samoa lock Tekori barged over for the opening try of the match, but Bezy missed the conversion leaving La Rochelle a point ahead.
James kicked his first penalty before La Rochelle stole a Toulouse line-out deep in their own half and broke at pace.
They spread the ball wide to the left, over to the right and then when it came back to the left, Fiji international forward Qovu blasted through wing Arthur Bonneval to score.
La Rochelle's huge pack then got the shove on from a five-metre lineout to push centre Aguillon over the line.
But Toulouse came straight back up the pitch to get their own pushover try through hooker Marchand.
The hosts dominated the final exchanges but couldn't force a game-winning try.
- Survival boost -
Stade Francais maintained their fine home form to boost their survival hopes with a bonus point 32-9 win over Bordeaux-Begles.
The bonus point was in the bag by half-time as the back three of Fiji flyer Waisea Nayacalevu, fullback Djibril Camara, with a mazy individual effort, and wing Jeremy Sinzelle all crossed the whitewash.
Jules Plisson kicked five penalties and a conversion while New Zealander Simon Hickey, with two penalties, and Ireland's Ian Madigan with one scored the visitors' points.
Hard-hitting Carl Fearns guided Lyon to an upset 16-3 victory over Montpellier in a bruising clash.
The English No.8, signed to play for Gloucester next season, inspired a pack that outmuscled that of a Springbok-laced Montpellier boasting the likes of the Du Plessis brothers, Bismarck and Jannie, in the frontrow, and Jacques du Plessis and Paul Willemse at lock.
Australian fly-half Mike Harris kicked two first-half penalties and a third in the second period for Lyon.
The sole try of a contest where physicality overshadowed subtly was scored by Tongan centre Hemani Paea in the 50th minute, Harris nailing the conversion.
Montpellier's points came from a Willie du Plessis penalty but their defeat further compounded coach Jake White's woes, with his side not able to notch up two consecutive victories since early December.
La Rochelle lead by four points as Clermont dropped to second due to a 26-16 loss at Castres on Saturday.
Last year's Top 14 finalists Racing 92 and Toulon also both lost, 19-10 to Grenoble and 15-5 to Brive respectively. Rock-bottom Bayonne held Pau to a 25-25 draw.