The Super Cup final of this season pits Barcelona against Real Madrid, their enduring rivals.
Real Betis was defeated by the Catalans on Thursday in the semifinal match after a penalty shootout.
To help Barca win 4-2, Marc-Andre ter Stegen turned away shots from Juanmi and William Carvalho.
After extra time, the score remained 2-2 in the game.
Nabil Fekir scored to tie the score after Robert Lewandowski took the early lead.
Ansu Fati gave Barca the advantage once more in extra time, but Loren Moron leveled the score for Betis.
Real Madrid, who defeated Valencia in a shootout on Wednesday, will now face Barcelona.
The championship is set for Sunday.
Related posts:
Real reason I turned down Real Madrid in favor of joining Barcelona
Zidane, a former manager of Real Madrid, declines a job coaching a new squad
Why are only half of a Brazilian legend's goals recorded, placing Ronaldo ahead of him?
I was publically reprimanded by Conte for two hours - Richarlison, the Brazilian super star