Clermont Auvergne had to settle for a draw against Racing 92, while Lyon held on to beat Pau in a thrilling day of Top 14 action.
Toulouse played almost an hour with 14 men but were still able to beat Racing 92 in a magnificent European Champions Cup quarter-final.
Toulouse are now unbeaten in 14 Top 14 matches after grinding it out at La Rochelle, while Racing 92 got the better of Bordeaux.
There were big wins for 2017-18 Top 14 finalists Castres and Montpellier on Saturday, with Benjamin Urdapilleta inspiring.
Leicester Tigers have confirmed England centre Manu Tuilagi has signed a new deal with the Premiership club.
Kieran Read had been linked with Racing 92 and a Premiership switch, but said it was a "pretty straightforward" decision to move to Japan.
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,
Eddie Jones says only Manu Tuilagi can decide his future amid reports he is set for a big-money move to the Top 14.
After agreeing to join Racing 92 until the end of the season, Dan Carter expressed his sadness at the circumstances surrounding his return.