The Reds were struggling to create any chances at the other end and, with another vital Barclays Premier League clash looming at Wolves on Sunday, Sir Alex opted to withdraw Rio Ferdinand and Michael Carrick. Chris Smalling and birthday boy Paul Pogba entered the fray.
No sooner had the substitutes come on, United went further behind as Athletic Club sealed their spot in the Europa League quarter-finals on 66 minutes. Iraola went on another marauding run down the right and although his cross was half-cleared by Smalling it fell to the feet of de Marcos, who brought the ball under control before blasting low past De Gea via a slight deflection off Jonny Evans. Cue more jubilant celebrations around the Estadio San Mames.
It nearly got worse for Sir Alex’s men when Susaeta screwed a shot just wide and Toquero headed over the bar. Instead, Rooney reduced the arrears with a consolation goal – a lovely curling effort from 25 yards that was sportingly applauded for its quality by the home fans.
No doubt Wayne would have traded a superb goal for a significant one as his effort couldn't alter the fact that United had been well beaten by the Bilbao club over two legs. Now Sir Alex will have to ensure there's no hangover for the pursuit of a 20th English title and that lessons are learned for next season's return to Europe.