Lionel Messi came in at second half and changed the whole game to claim huge win.
Messi does not feature in the starting line-up for Barca in LaLiga for the first time in over a year. The Argentine is one of three changes from the win over Kiev during the week.
Dembele replaces him in the final third, while Sergi Roberto gets the nod ahead of Dest at right back.
Lenglet slots back into the defence, allowing De Jong to push forward. Pjanic makes way from the midfield.
FC Barcelona: Marc-Andre ter Stegen; Sergi Roberto, Gerard Pique, Clement Lenglet, Jordi Alba. Frenkie de Jong, Sergio Busquets, Pedri; Ousmane Dembele, Antoine Griezmann, Ansu Fati.
SUBS: Sergino Dest, Carles Alena, Miralem Pjanic, Martin Braithwaite, Lionel Messi, Riqui Puig, Neto. Trincao, Junior Firpo, Oscar Mingueza, Konrad De la Fuente, Arnau Tenas.
Real Betis: Claudio Bravo; Emerson, Aissa Mandi, Marc Barta, Alex Moreno; William Carvalho, Guido Rodriguez. Sergio Canales; Joaquin, Antonio Sanabria, Cristian Tello.
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