Toulouse rout Stade
Clerc, 34, scored twice to take his club career try total to 97, just three behind the all-time record of 100 held by Laurent Arbo.
In all, Toulouse ran in five tries for a bonus-point win which allowed them to open up an eight-point gap on seventh-placed Castres and well-placed for the end of season play-offs.
Earlier Sunday, Clermont went five points clear at the summit by coming from 19-0 down to defeat Bordeaux 24-19.
Toulouse had been co-leaders of the Top 14 at the end of January but with a host of stars away on Six Nations duty, they suffered a five-game run without a victory to fall badly off the pace.
In stark contrast, defending champions Stade remain third from bottom although they do have the attraction of a European Cup quarterfinal against Leicester on the horizon.
Their chances on Sunday were not helped by having 15 players sidelined through injury.
"After a complicated period, five points against the champions - albeit they were under strength and have priorities elsewhere - it was a successful evening," said Toulouse coach Ugo Mola.
"We had been in crisis but our enthusiasm has returned."
Stade backrower Rafael Lakafia was blunt in his assessment.
"We have to be conscious of our reality today - reaching sixth place and a play-off place is mission impossible."
Springboks flyhalf Morne Steyn gave Stade an early lead with a penalty which was quickly cancelled out by Luke McAlister.
Steyn was then yellow carded on the half-hour mark as Stade buckled in front of their posts with the referee awarding a penalty try as the home forwards hammered away.
Sebastien Bezy added the extras before Clerc slalomed to a second try of the first half after being smartly set up by forwards Louis Picamoles and Imanol Harinordoquy carving out the opening.
It was Clerc's 96th career club try, taking him just four away from the all-time record held by former Montpellier and Castres star Arbo.
Bezy again hit the conversion as Toulouse led 17-3 at the break although their joy would have been curtailed by seeing Picamoles - just back after suffering a groin injury in France's Six Nations opener against Italy - limp off.
Toulouse grabbed a third try 10 minutes into the second half.
Fullback Maxime Medard caught a slumbering Stade defence napping with a quick tap penalty, sprinting away before freeing Alexis Palisson who spun off two tackles for the score and 22-3.
Clerc added his second of the night from close range in the 73rd minute after a crossfield kick had allowed Toulouse to have four attackers ranged against just one defender.
Medard grabbed a deserved try in the last minute with Bezy again popping over the extras.
Bordeaux had to make do with four Pierre Bernard penalties in the first half against Clermont, but they finally broke down the disciplined away team through second row Berend Botha's try to move 19-0 ahead.
Patricio Fernandez kicked a penalty to get Clermont on the board beforeAlivereti Raka scored a converted try for the leaders.
Three minutes later Fernandez converted his own score to make it a two-point game.
Wesley Fofana, in his first club match after returning from international duty, conjured up a well-taken try to seal a thrilling victory for Clermont.
"It was interesting at 19-0 that we did not go mentally. We had the resources, great heart, and the spirit to come back without panicking," said Clermont coach Franck Azema.
Results:
Bordeaux-Begles 19 Clermont 24
Toulouse 36 Stade Francais 3
Racing 20 Toulon 21
Agen 21 Montpellier 45
Brive 23 Castres 22
Grenoble 39 La Rochelle 23
Pau 25 Oyonnax 6
Agence France-Presse