Los Leones, who are also due to play last year's final against Real Sociedad this April, will be looking to script history with another berth in the showpiece clash.
They have reached this far with a great deal of effort, narrowly seeing off Ibiza and Alcoyano before ousting top-flight rivals Real Betis on penalties.
Having avoided both Sevilla and Barcelona in the last four, Marcelino Toral must be dreaming of more title glory this season. They already clinched the Spanish Super Cup last month.
Levante, in fine form lately, will be looking to spoil their party as they're on the cusp of reaching their first-ever League Cup final.
The Granotas haven't lost in all competitions since the 2-1 defeat to Villarreal on 2 January, and have been impressive in the cup too.
They've struck 13 times in four games so far, including a thumping 4-2 win on the road to Real Valladolid before ousting Villarreal 1-0 at home.
Athletic Bilbao vs Levante Head-To-Head
Athletic Bilbao have traditionally dominated this fixture, winning 17 times from 25 clashes with Levante, who have beaten them on just six occasions.
In the first leg of their league clash this season, Bilbao snatched a late 2-0 win at home, and will be hoping for a repeat of the same here.
Athletic Bilbao Form Guide (all competitions): W-W-L-D-D
Levante Form Guide (all competitions): D-W-W-W-D
Athletic Bilbao vs Levante Team News
Peru Nolaskoain is a long-term absentee with a sprained ankle. Meanwhile, Mikel Balenziaga suffered a knock last month and will miss out.
Inigo Vicente tested positive for COVID-19 last week and will remain in isolation.
Injured: Peru Nolaskoain and Mikel Balenziaga
Unavailable: Inigo Vicente
Jose Campana is out with a muscle injury and isn't expected to return until April, while Nikola Vukcevic is nursing back pain.
Injured: Jose Campana and Nikola Vukcevic
Athletic Bilbao vs Levante Predicted XI
Athletic Bilbao (4-4-2): Unai Simon; Inigo Lekue, Yeray Alvarez, Inigo Martinez, Yuri Berchiche; Oscar de Marcos, Dani Garcia, Iker Muniain, Alex Berenguer; Asier Villalibre, Raul Garcia.
Levante (4-2-3-1): Dani Cardenas; Coke, Sergio Postigo, Ruben Vezo, Tono; Nemanja Radoja, Mickael Malsa; Son, Ruben Rochina, Enis Bardhi; Roger Marti.
Athletic Bilbao vs Levante Prediction
This will be an enticing clash as both sides have been in good form in 2021. There will be plenty of goalmouth action and we expect this to be an entertaining match.
Bilbao do not lose easily at home, and we expect a narrow win for them, with all to play for in the second leg.
Prediction: Athletic Bilbao 2-1 Levante