Last year’s Champions League finalists, who arrived in Spain trailing 3-2 from the first leg, were undone by a stunning first-half volley from Fernando Llorente and a deflected strike from Oscar de Marcos as Athletic won 2-1 on the night.

United striker Wayne Rooney scored a superb 80th-minute consolation goal but the damage had already been done as the enthusiasm and talent of La Liga’s seventh-placed side proved too much for the English champions.

Athletic will be joined in the last eight of the continent’s second tier competition by fellow La Liga side Valencia, who drew 1-1 at PSV Eindhoven to go through 5-3 on aggregate, and Hanover 96, who beat Standard Liege 4-0 for a 6-2 aggregate win.

AZ Alkmaar also progressed despite going down to 10 men after only two minutes and falling two goals behind after just 15 at Udinese. However, they managed to pull a goal back for a 2-1 defeat that saw them squeeze through 3-2 on aggregate.

Later on Thursday, United’s Premier League title rivals Manchester City will be seeking to overturn a 1-0 first-leg deficit when they host Sporting.

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