Clermont was a cut above Bordeaux in a 40-20 success, although the visitors' hopes were hindered by a red card for Blair Connor in the 53rd minute.
Alexandre Fischer, Peceli Yato, Paul Jedrasiak and Alexandre Lapandry each scored tries and Greig Laidlaw was instrumental with the boot.
Toulouse can reclaim top spot by beating Racing 92 on Monday (AEDT).
It has been a miserable season for Perpignan but at the 16th time of asking it finally earned a Top14 win in a 28-10 triumph at Montpellier.
Jean Bernard Pujol scored the visitors' only try, while Enzo Selponi kicked 23 points in an expert display off the tee to give Perpignan that rare winning feeling.
Rudi Wulf and Noa Nakaitaci both dotted down as Lyon ran out a 24-13 winner at fellow top-six hopeful Stade Francais.
Toulon was a narrow 33-30 winner over Stade Francais last time out in Top14, but it was another lacklustre outing in a 19-10 reverse at Agen this time around.
Tries from Antoine Miquel and Benito Masilevu coupled with nine points from Leo Berdeu's boot had Agen 19-3 up and, despite Francois Trinh-Duc's late consolation, Toulon failed to claw back the deficit, and has now lost three of its past four league outings.
Rounding out the action, Castres earned a narrow 14-9 triumph at Pau.