Lock Faasalele was dismissed for a dangerous tip tackle on Gabriel Ngandebe after only 17 minutes at GGL Stadium, with Montpellier already leading 21-3 at the time.
Vern Cotter’s men ran riot to rout a Toulouse side that had won three and drawn one of their first four games, scoring 10 tries in a devastating display.
France number eight Picamoles, Ngandebe, Nemani Nadolo, Ruan Pienaar and Benjamin Fall went over in a first half that ended with Montpellier leading 31-3.
Last year’s runners-up showed no mercy after the break. Nadolo and Fall touched down again and Picamoles added another three, with Pienaar scoring 10 points from the tee and Johan Goosen slotting the extras on three occasions.
Two Arthur Bonneval tries were no consolation for 14-man Toulouse as they were put to the sword.
Stade made it four wins in five with a 25-13 triumph over Pau, Gael Fickou helping himself to another brace.
Watisoni Votu’s second-half double gave Pau hope, but they gave themselves too much to do.
Watch: Beyond 80 ‘Knocked’ – RugbyPass documentary looks at concussion
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