Bordeaux came back from an 11-point deficit to defeat Toulon 28-23 in the Top 14 at the Stade Chaban Delmas.
Newcastle, Exeter, London Irish, Cardiff and Connacht recorded bonus-point wins in the Challenge Cup.
Jake White's first game in charge of Montpellier ended in a win over Toulon, while Stade Francais hung on to top spot.
Stade Francais shocked defending champions Toulon 30-6 to end the year at the summit of the Top 14.
Wins for Toulon and Clermont at the weekend has kept the race for top spot alive in France's Top 14.
Stade Francais took over the leadership of the French Top 14 on Friday with a five-try 43-30 victory at Grenoble.
Grenoble will be looking to keep their unbeaten home record intact when they host Stade Francais in the Top 14 on Friday.
Dewi Morris says the Top 14 is growing in stature, and will keep doing so with the inclusion of Dan Carter.
Saturday proved to be a Premiership party in the Challenge Cup, with wins for Exeter, London Irish and Gloucester.
Round Four of the European Rugby Challenge Cup continues on Saturday, with six fixtures on the cards.
Newcastle host Stade Francais, Brive take on Oyonnax and Rovigo visit Grenoble
Reigning Top 14 champions Toulon claimed a 27-19 victory against Clermont Auvergne in a clash of the titans on Saturday.
A depleted Toulon team came a cropper at Castres, allowing Clermont Auvergne to take over as new leaders in the Top 14.
The final of the Top 14 will be held at Barcelona’s Nou Camp at the end of the 2015-16 season.
Toulon ran in nine tries as they eased to a 61-28 victory over Grenoble at the Stade Mayol to move to the Top 14 summit.
London Irish made it two wins from two in the Challenge Cup as they battled past Grenoble 25-15 in France.
Friday sees five games in Round 2 of the newly-formed European Rugby Challenge Cup, including Dragons against Newcastle.
Cardiff Blues kicked off their European Rugby Challenge Cup campaign with a 37-14 bonus-point victory over Grenoble.
There are seven European Rugby Challenge Cup matches across Saturday and Sunday. Sky Sports previews them all.
Gaetan Germain missed a late conversion as Grenoble held on to defeat Brive 26-25 in their Top 14 clash at Stade des Alpes.
With the Six Nations on a two-week sabbatical, we take a look at the championship so far.