Four years have passed since Lionel Messi last reached a Champions League semi-final and his drought has become a source of unease for Barcelona ahead of their latest attempt on Tuesday.
Into the final of the Copa del Rey and with a comfortable 11-point lead at the top of La Liga, Barca coach Ernesto Valverde is expected to give a number of fringe players a chance when they visit bottom side Huesca on Saturday.
Lionel Messi finished with a bloody nose and swollen cheek but Barcelona left unscathed, with one foot in the semi-finals and Manchester United hoping for another Champions League miracle.
The five-time European champions will face either Liverpool or Porto in the last four in their first appearance at the stage of the competition since 2015.
Luis Suarez's 12th minute back-post header was deflected past David de Gea by United left-back Shaw.
Lionel Messi has a history of terrorising Manchester United but Ole Gunnar Solskjaer believes it is not impossible to stop the Barcelona star inflicting more damage in Wednesday’s Champions League quarter-final.
Barcelona might have their eighth title in 11 years all-but sewn up but, with six games left to play, La Liga is far from finished.
Lionel Messi clinched an eighth La Liga title for Barcelona in 11 seasons on Saturday as he scored the only goal in a 1-0 win at home to Levante.
Barcelona are closing in on their eighth La Liga title in 11 years after Clement Lenglet and Jordi Alba both scored in a 2-1 win over Real Sociedad on Saturday.