Alaves matched the greatest feat in the Spanish club's history by reaching the final of a major competition after defeating Celta Vigo 1-0 in the semifinals of the Copa del Rey on Wednesday.
Following a 0-0 draw in the first leg in Vigo, midfielder Edgar Mendez scored an 82nd-minute winner to give the Basque Country club a surprise spot in the May 27 final against two-time defending champion Barcelona, who edged Atletico Madrid 3-2 on aggregate on Tuesday.
"We made history today," Alaves captain Manu Garcia said. "And in the final in May we will seek glory."
Alaves stunned Barcelona with a 2-1 win at Camp Nou in the third round of La Liga matches earlier this season, and the teams will meet again in the league on Saturday.
Alaves' only previous final was a 5-4 loss after extra time in a thriller against Liverpool in the 2001 UEFA Cup, the competition now known as the Europa League.
Founded in 1921, Alaves were promoted to the top flight of the Spanish league this season after 10 years in the lower divisions, including four in the third tier.
"Not even in our greatest dreams did we imagine something like this," Alaves midfielder Kiko Femenia said. "But we deserved it after all that we have done until now."
A four-time runner-up in the Copa, Celta was trying to return to the final for the first time since 2001. It entered the semifinals boosted by a victory over Real Madrid in the quarterfinals.
"We had our chances but we couldn't capitalize on them," Celta coach Eduardo Berizzo said. "We know that these games are decided by details and you pay when you make a mistake. We are disappointed. This loss hurts, but we have to move on."
Mendez netted the winner only three minutes after coming off the bench. He picked up the ball outside the area and beat three Celta defenders before hitting a shot over goalkeeper Sergio Alvarez as he charged from his line at Mendizorroza Stadium in northern Spain.
Alaves dominated possession throughout the game and had most of the scoring opportunities, while Celta threatened only a few times on counter-attacks.
The venue of the final still hasn't been set, but it's likely to be held in Madrid.
Alaves had tried to postpone Wednesday's match because Celta got to rest last weekend as their league game against Madrid had to be called off due to bad weather.