There were big wins for 2017-18 Top 14 finalists Castres and Montpellier on Saturday, with Benjamin Urdapilleta inspiring.
Kieran Read had been linked with Racing 92 and a Premiership switch, but said it was a "pretty straightforward" decision to move to Japan.
A 28-9 victory over Stade Francais saw Top 14 leaders Toulouse break a league record as they extended their unbeaten run to 12 games.
Toulouse's lead in the Top 14 table is down to a solitary point after Clermont Auvergne thrashed Grenoble. Lyon, meanwhile, lost at home.
Lyon claimed a third successive win and are breathing down Clermont's necks after beating them at Matmut Stade de Gerland,
Zack Holmes scored 15 points as Toulouse extended their lead at the Top 14 summit, while Stade Francais boosted their play-off hopes.
Eddie Jones says only Manu Tuilagi can decide his future amid reports he is set for a big-money move to the Top 14.
Having sustained a suspected concussion while playing for Top 14 at the weekend, Sergio Parisse will sit out Italy's clash with Ireland.
Mourad Boudjellal told Julian Savea he is not welcome at Toulon, but the ex-All Black promised to keep giving his all for the team.
After agreeing to join Racing 92 until the end of the season, Dan Carter expressed his sadness at the circumstances surrounding his return.
For the second time in the space of 24 hours, a Toulon player has defended himself following comments made by president Mourad Boudjellal.
Racing 92 ran out of time in their defeat to Toulouse, while La Rochelle survived a Top14 scare against lowly Grenoble.
Racing 92 have some pretty formidable back-up for Finn Russell with Dan Carter returning to the Top14 club.
Perpignan finally had a win to celebrate, while Clermont Auvergne were too good for Bordeaux-Begles in Top14.
Toulouse replaced Clermont Auvergne at the summit of the Top 14 table on Sunday, while Toulon scored two late tries to stun Stade Francais.
Clermont had not been beaten since October, but they were brought back down to earth by Top 14 champions Castres.