Football Espana and The Spanish Football Podcast relayed the decision made after the France international was given his marching orders in the 4-0 win at the Camp Nou:
The ban means Dembele will not be available for the showdown with Eibar on Saturday, October 19. In addition, he will sit out the first Clasico of the campaign, with Madrid due to travel to Barcelona on October 26.
Per Spanish football writer Jason Pettigrove, there's not yet been any indication as to whether Barcelona will appeal the decision:
Dembele was the second player to be sent off for Barcelona in the win after Ronald Araujo had fouled Javier Hernandez when the Sevilla striker was through on goal.
Per Football Espana, Dembele is then said to have told referee Antonio Lahoz he was "very bad" moments after the decision, prompting the official to issue the 22-year-old a second yellow card.
Dembele's Barcelona team-mate Lionel Messi came to his defence after the incident, noting that the France international hasn't yet got a full grasp of the Spanish language:
For the winger, the dismissal and subsequent ban represents another setback in what's been a stop-start time at Barcelona.
While Dembele has shown flashes of the ability that prompted Barcelona to sign him in 2017, injuries and inconsistency of form have prevented him from cementing a spot in the side under manager Ernesto Valverde.
With Antoine Griezmann left on the bench on Sunday, Dembele had the chance to stake a claim for a regular spot, and he did brilliantly to net Barcelona's third goal:
But now he's set for another stint on the sidelines when it comes to domestic matches, and he'll be disappointed to miss what's shaping up to be a significant Clasico contest.
Real Madrid and Barcelona are first and second in the Spanish top flight, respectively, with both sides recovering from ropey starts to the campaign. The Blaugrana trail their great rivals by two points after eight games of the season.