The Frenchman needed just seven minutes to open the scoring in the game as he took it upon himself to fill the shoes of Lionel Messi and Luis Suarez, who were both rested.
The goal came about from an error by youngster Kyle Walker-Peters, who was making his Champions League debut for the visitors.
The defender was caught in possession by Dembele on halfway and even though he got back in to challenge, he was then left for dead by a brutal turn of pace from the former Borussia Dortmund man.
Dembele burst past Walker-Peters as if he wasn't there, before keeping his cool to chop inside Harry Winks' attempted sliding challenge and side-foot an effort below Hugo Lloris and into the back of the net.
The goal is Dembele's ninth of the season in 20 appearances in all competitions.
December 11, 2018