Athletic Bilbao comfortably beat Atletico Madrid to set up a Copa del Rey final against Mallorca on 6 April.
Alejandro Berenguer's first-half penalty gave Athletic a 1-0 away victory in the first leg on 7 February.
Athletic doubled their advantage after 13 minutes of the home second leg when Nico Williams set up Inaki Williams.
The pair combined again for the second goal, with Nico Williams scoring just before half-time, and Gorka Guruzeta scored to seal the 4-0 aggregate win.
The second leg took place in front of 52,061 at San Mames, the highest attendance in Athletic's history.
The restart after half-time was delayed because of a medical emergency in the stands.
In a post on X, Athletic wrote: "A person was asphyxiating and, thanks to the medical services, was stabilised and taken to hospital."
The final will be played at the Estadio La Cartuja in Seville with the winners qualifying for the Europa League group stage for 2024-25.
Mallorca won the Copa del Rey in 2003 after losing in the final in both 1991 and 1998 and reached this year's showpiece with a 5penalty shootout win over Real Sociedad after it finished 1-1 on aggregate following the second leg.
Mallorca are 16th in La Liga and only six points above the relegation zone, while Athletic are fifth, one place behind Atletico in fourth.
Athletic, who have won the Copa del Rey on 23 occasions, defeated Barcelona 4-2 in the quarter-finals after Atletico had beaten Real Madrid by the same score a round earlier.
Source: BBC