Winger Donovan Taofifenua's late bonus point-claiming try sent Racing 92 back to the summit of the French Top 14 despite Saturday's 23-18 loss at Clermont.
Taofifenua crossed in the 78th minute to bump Racing one point above Toulon, who beat Pau 36-16 earlier in the day to originally grab top spot.
Tonga centre George Moala and Argentina winger Bautista Delguy scored for the hosts in central France as Clermont secured their fourth win from nine games this season.
The unlikely bonus point gives Siya Kolisi's Racing a further boost before starting their Champions Cup campaign against Harlequins next Sunday having rested the two-time Rugby World Cup-winning captain for the Clermont trip.
Racing trailed 17-6 at the break after Moala and Delguy's efforts and former Pumas fly-half Benjamin Urdapilleta's points from the tee.
Fijian No.8 Kitione Kamikamica sparked Racing's revolt with nine minutes to play before Taofifenua, who came through Clermont's academy, dived over spectacularly in the corner in the dying moments.
Earlier, Toulon fly-half Enzo Herve stepped in for the injured ex-Wales international Dan Biggar and scored 21 points including two tries in the Pau victory.
Herve claimed his double within 13 minutes in glorious sunshine on the Cote d'Azur before tries from prop Dany Priso, France winger Gabin Villiere and back-rower Paul Abadie's 80th-minute effort.
- 'Back to work' -
Next up for Toulon is hosting Exeter Chiefs in the opening round of the Champions Cup on Saturday, having won the last of their continental titles in 2015.
"Claiming the bonus point at the end of the game was important," Toulon assistant coach Sergio Parisse told reporters.
"We know we can lose every weekend, so we have to get back to work on Monday to keep this positive energy by changing competition," the ex-Italy captain added.
Ronan O'Gara's La Rochelle eased past lowly Perpignan 35-6 ahead of the defence of their Champions Cup title. They begin their quest for a third straight crown by hosting Irish province Leinster in a rerun of last season's final.
Bernard Laporte's Montpellier remain bottom after the controversial former French rugby federation president and ex-France head coach lost his second game in charge as they were beaten 34-19 at Bayonne.
Laporte's side have lost eight consecutive league games, their worst run since billionaire owner Mohed Altrad took over the club in 2011.
On Sunday, title holders and record 22-time champions Toulouse go to Paris to play Stade Francais, winners on 14 occasions, as the country's two most successful sides meet at a packed Stade Jean-Bouin.
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