Atletico Madrid sprung a surprise in the Spanish Super Cup by staging a thrilling comeback to beat Barcelona 3-2 on Thursday and set up a final against Real Madrid.
Barca looked on course for a Sunday showdown against Real when they led Atletico 2-1 with nine minutes left but instead it will be a Madrid derby in Saudi Arabia to decide who lifts the trophy.
All five goals were scored during a wild second half in Jeddah that began with Koke putting Atletico in front, just 21 seconds after coming on as a substitute at the interval.
Goals from Lionel Messi and Antoine Griezmann turned the game on its head, only for Atletico to hit back with a late double, Alvaro Morata converting a penalty in the 81st minute before Angel Correa found a winner in the 86th.
In between, Barcelona also had two goals ruled out after VAR spotted tight offsides while Atleti were denied what looked a clear penalty at 2-2, after the ball clipped the hand of Gerard Pique.
A pulsating contest will have delighted the Spanish Football Federation, who have faced heavy criticism for taking the competition away from Spain to a different continent, and a country that has a long-condemned record on human rights.
Barcelona coach Ernesto Valverde said on Wednesday he preferred the old format but his strong team selection, that included Messi, Griezmann and Luis Suarez, suggested this was a tournament he was eager to win.