Barcelona must win against Athletic Bilbao to qualify. I propose here a tip with confidence 10/10. See below what it is.
Barcelona

Do not cross the best shape.
He lost the first leg in Bilbao (1-2) and in the last round of La Liga only took a point at Villarreal (1-1).
Start big favorite at Unibet (L1160657W000330) in this game.
We find it in second place in La Liga, remote rather than Real Madrid.
He won the last three home games, scoring at least three goals each time.
In King’s Cup has won the last 13 matches played at the Camp Nou.
Probable team: Ter Stegen – S.Roberto, Pique, Mascherano, J.Alba – Busquets, Iniesta, D.Suarez – Messi, L.Suarez, Neymar.

Athletic Bilbao

We find it seventh in La Liga.
He impressed on tour, but disappointed in the last round of the championship, they drew at home to Alaves (0-0).
Form of time is still good. He lost one game in the last nine played.
Defense is the strong point this season, one of the strongest in La Liga.
No Win 18 matches at Camp Nou.
Probable team: Iraizoz – Bóveda, ETXEA, Laporte, Balenziaga – San Jose, Benat – Williams, Eraso, Iker Muniain – Aduriz.

Direct meetings:

219 or have met these bands.
The Catalans have won 109 games, while his opponent was imposed 74 times.
Twice they faced this season, sharing the victories.