Fernando Llorente scored late as Athletic Bilbao overcame a first-leg deficit to beat Sporting Lisbon and set up an all-Spanish Europa League final with Atletico Madrid after the 2010 champion finished off Valencia on Thursday.
Llorente grabbed the 88th-minute decider after setting up two goals to give Bilbao a 3-1 win at San Mames Stadium for a 4-3 aggregate score.
The Spain striker assisted on goals by Markel Susaeta and Ibai Gomez, while Ricky van Wolfswinkel scored for Sporting to keep the result in doubt until Llorente used his wide frame to hold off his marker and score with a fine touch from close range.
After resisting Valencia's first-half push, Adrian Lopez netted in the 60th to give Atletico a 1-0 win as it eased into the May 9 final in Bucharest, Romania, on a 5-2 combined advantage.
While Chelsea and Bayern Munich spoiled an all-Spanish Champions League final by eliminating Barcelona and Real Madrid this week, Bilbao made sure Spain will have a winner of Europe's second-tier club competition.
"This is incredible. It's the first time that I have wanted to cry on the pitch," said Llorente as his teammates celebrated with their fans. "This is beyond words. This is the best!"
Bilbao, which eliminated Manchester United and Schalke to reach the semifinals, will play its first European final in 35 years after the Basque club lost the 1977 UEFA Cup to Juventus.
"We made history tonight, and I hope we continue to do so in the final, which I hope we can win because these players and these fans deserve it," Llorente said.
Llorente caused Sporting trouble from the start and produced Bilbao's 17th-minute opener by chesting a pass back for Susaeta to beat goalkeeper Rui Patricio with a bouncing shot.
The visitors leveled when Van Wolfswinkel fired in a rebound just inside the edge of the box in the 44th.
Sporting looked set to go into halftime ahead on aggregate until Llorente received the ball, turned and flipped a pass behind the defense for Gomez to slot by the charging Patricio in stoppage time.
Bilbao defender Javi Martinez hit the post with a header and Sporting's Emiliano Insua smashed a long strike off the base of the goal frame at the restart as both teams looked to break the aggregate stalemate.
The game appeared destined to go into added time until Llorente rode his defender and flicked Gomez's short cross off the post and into the net for his seventh goal of the tournament.
"They were better in the first leg, but we knew that here at San Mames it would be a different story," Susaeta said. "It was too bad they scored, but the good thing is that we kept trying and at the end we got the goal we were looking for."
Bilbao will also play Barcelona in the Copa del Rey final.
Needing to rally from a two-goal deficit, Valencia set a frenetic pace in the first half at Mestalla Stadium.
Valencia forward Jonas drew a reflex save from goalkeeper Thibaut Courtois in the 21st, while Atletico was limited to an Arda Turan's pass destined for the unmarked Radamel Falcao that goalkeeper Diego Alves was quick to intercept.
Valencia midfielder Sergio Canales had to be taken off the pitch in a stretcher in the 58th after apparently injuring the same right knee that had him sidelined for six months this season with torn ligaments.
Two minutes later Adrian put to rest any thoughts of a Valencia fightback with a superb shot from the right flank that whipped around the goalkeeper and into the far side of the net.
"We knew the injury to Canales would be a blow for them," said Atletico coach Diego Simeone, who won the 1998 UEFA Cup with Inter Milan.
"They had control of the game and pressed us, but we made a tactical change and in the second half we didn't have many problems. As the game wore on spaces opened up and that's when Adrian scored his great goal."
Atletico played the final 10 minutes a man down after Thiago was shown a red card for tussling with Valencia's Jordi Alba and Soldado.
Atletico also ousted Valencia from the 2010 quarterfinals on its way to winning the tournament.