South African Rugby World Cup winner Cheslin Kolbe scored his sixth try in as many games this season as Toulouse won 30-24 at European Champions Cup finalists Racing 92 in the French Top 14 on Saturday.
Kolbe crossed in the first half, with a perfect display from the tee by flyhalf Thomas Ramos against a much-changed Racing ahead of next Saturday's continental showdown with Exeter Chiefs in Bristol.
"He's in top form. A great player who made the most of confinement to rest. He's started the season very well, he's key for us," Toulouse defence coach Laurent Thuery said.
The game was played under the cloud of an off-the-field political row in French rugby between the league running professional rugby (LNR) and the federation (FFR) regarding extra Tests matches this autumn.
The dispute escalated further on Saturday as the LNR said the 31-man France squad named by national coach Fabien Galthie earlier this week to host Wales on 24 October was "null and void".
The FFR responded with their own letter reminding the LNR of its obligation to release players for international windows designated by global body World Rugby.
"What's important is that rugby wins from the situation. For the France national team to be strong, the clubs have to be strong," Racing coach Laurent Travers said.
Back on the pitch, Travers made 12 changes from the European semi-final win two weeks ago, but France squad members Olivier Klemenczak and Teddy Thomas as well Ireland lock Donnacha Ryan kept their places.
Travers' Toulouse counterpart Ugo Mola started all but one of his eight les Bleus squad members as hooker Julien Marchand was rested and fullback Ramos moved to outside-half, with Romain Ntamack starting at inside centre.
The visitors led 7-3 after 11 minutes as winger Matthis Lebel scored directly from Ramos' restart after Maxime Machenaud had opened the scoring with a penalty goal.
France scrumhalf Machenaud slotted two further penalties before Kolbe touched down to keep his impressive early season scoring record after Ntamack orchestrated a break on the outside.
Ramos added a penalty before Klemenczak set up Donovan Taofifenua to slalom his way through for his first senior try and Machenaud's conversion cut the deficit to 17-16 at the break.
Travers' men reclaimed the lead three minutes after the interval as former France under-20s No 8 Jordan Joseph crashed over but Australian Zack Holmes restored the lead with half an hour to play and Ramos' extras made it 24-21.
Francois Trinh-Duc and Ramos traded penalties to make it 30-24 with five minutes to go but the visitors held out to remain top of the table as the hosts lost their first game of the campaign.
Earlier, Kolbe's fellow World Cup winner Eben Etzebeth made his return from a rib injury in Toulon's 25-21 win over Montpellier.
Clermont's trip to Bordeaux-Begles scheduled for Sunday was postponed due to the hosts recording coronavirus cases, but Lyon's visit to Pau goes ahead.