The 20-year-old made history in 2015 by becoming the youngest player to captain a team in a UEFA Champions League match (at age 18 years and 221 days).
The news will likely fuel reports of Pogba and Mourinho's uneasy relationship, particularly given the manager's rant in Friday's news conference. All eight players ruled out with injuries and Paul Pogba also missed the contest from falling ill overnight.
They then had four senior players interviewed by Spanish police over the alleged theft of a taxi from outside a fast-food restaurant in Barcelona. "When he went to Inter [Milan], he brought Walter Samuel from Spain, he'd had a bad experience I think at Real Madrid".
"Now is the time to think about Paul, to know what happened, why he didn't feel good enough to play, can he play or be available to help us on Wednesday", said Mourinho.
"We have all the squad fit and it will be another game to provide players with the chance to compete on Wembley and we have the possibility to reach the quarter finals".
Lukaku netted his second goal of the game and 21st of the season in all competitions 10 minutes after the break to put United in firm control of the game. They always had attacking players and encouraged people to attack.
Pogba was reportedly unhappy at being played too deep in midfield, but Mourinho took exception to those reports.
Against Tottenham last month, at Wembley, Manchester United were well and truly outplayed by Mauricio Pochettino's men.
"There was a problem in terms of selection because of the incident to go with my strongest team", said Pardew."I chose to do that". Mourinho is right about Pogba's recent dip in form, but while Nemanja Matic, Michael Carrick and Scott McTominay offered plenty of defensive protection, there was precious little creativity in his absence.