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.
Toulon may have been at a numerical disadvantage for most of the second half but they still managed to defeat Top 14 leaders Toulouse.
Paul O'Connell has been linked with Toulon, but the outgoing Stade Francais forwards coach says he will not join another club next season.
Toulouse are now unbeaten in 14 Top 14 matches after grinding it out at La Rochelle, while Racing 92 got the better of Bordeaux.
Tries from Carl Fearns, Mickael Ivaldi and Thibaut Regard helped Lyon get back to winning ways in Saturday's Top 14 action.
The Top 14's leading two both won on Sunday, but it was Toulouse's bonus-point success that grabbed the attention.
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.