Barcelona past Athletic Bilbao 2-0 and into the Spanish Super Cup final on Wednesday.
Gavi scored in the 17th minute of the semifinal for his first goal since the midfielder returned to playing in October after a serious leg injury that sidelined him for nearly a year.
Gavi then helped Yamal put the result away in the 52nd with a pass that the 17-year-old controlled while twirling toward the goal. Yamal sized up goalkeeper Unai Simón and slotted home to double the lead.
Real Madrid and Mallorca will play the other semifinal also in Jeddah, Saudi Arabia, on Thursday. The final is on Sunday.
Yamal didn't reveal which rival he would prefer for the final, saying “the final will be tough, and we want to win it, that is the important thing.”
Gavi got Barcelona going after he redirected in a short pass from Alejandro Balde after the left back had reached the endline in Athletic's area.
Athletic could barely muster a threat until it was behind by two goals. Iñaki Williams thought he had scored in the final minutes but it was waived off after a video review ruled him offside.
The loss ended a 15-game unbeaten streak for Ernesto Valverde's team across all competitions.
Athletic was participating in the tournament as the winner of last season's Copa del Rey. Barcelona is here as the Spanish league's runner-up. The minor trophy has become a major cash maker for the federation and competing clubs since the federation struck a deal in 2019 to hold it in the Middle Eastern kingdom.