Clermont ran in five tries as it hammered Castres 41-6 at Stade Marcel Michelin and now holds a three-point advantage at the top of the table.

After Rory Kockott's penalty for the visitors began the scoring, Damian Penaud, Peter Betham and Alivereti Raka all crossed before the half-hour mark.

Judicael Cancoriet and Peceli Yato touched down after the restart, with Laidlaw successfully converting every try and adding two penalties to finish with 16 points.

Sekou Macalou's late score handed Stade a 25-20 home win against Montpellier, who had Aaron Cruden in inspired form.

Cruden converted his own try and added the extras to Kevin Kornath's score in the 71st minute to put Montpellier two points ahead.

However, Macalou went over four minutes from time ensure Stade did not slip any further adrift of Clermont.

Antoine Dupoint scored a second-half hat-trick as Toulouse earned a bonus point in a 36-18 success at Perpignan.

Toulouse trailed at the break, but Dupoint crossed for three of four away tries after the restart to turn the match in his side's favour.

Racing 92 enjoyed a big win as it beat Pau 48-28, while Agen and Grenoble drew 9-9.