He will ask his players to "help" against Claude Puel's side while accepting many of his key players may be undercooked for a game that he feels has come too soon after a World Cup summer.
On Thursday, Mourinho seemed to dismiss the chance of United signing anyone in the last knockings and yet reports emerged of enquiries for Jerome Boateng and Diego Godin, amid similar interest in Harry Maguire and Toby Alderweireld.
"I want to say a nice word, we were unlucky to get the Friday match as we could get the Sunday", he bemoaned at opening the campaign.
"The Red Devils finished runners up last season, but I don't think they will emerge as realistic title contenders or neighbours City's biggest challengers for the title this season".
If he remains at Old Trafford beyond the 31 August European transfer deadline how do the club, and Mourinho, manage the World Cup-winning star?
That will hardly have endeared Martial, who was left out of the weekend friendly against Bayern Munich, to Mourinho, although the manager insisted that omission was not a punishment.
"In pre-season it looked like I was saying something absolutely out of order, it looked like I was saying something insane", he added.
U.K.'s Boris Johnson facing Tory party investigation over burqa comments
She's one of 100 women who wear a niqab or burka who are calling for Mr Johnson to be kicked out of the Conservative Party. Johnson remains a backbench member of Parliament and contender to replace May in a future contest for power.
"You try to make a case and there is no case in it".
"When you are nine days without one minute of training or football, you go back and start with the other people".
The Red Devils kick off the new season at Old Trafford with Mourinho juggling a number of injury worries, while many of his players only returned to training at the start of the week following their World Cup exploits.
Mourinho was left irritated by the lack of signings, says the Guardian, as his bosses believed the targets were no better than the players he already had. He's a midfield player that technically is very good. Even though we have improved a lot, we need to keep improving.
"One lie repeated 1,000 times is still a lie, but the perception of people is that it's true".
"I like my players and my group".
And the wait is finally over, as the Premier League is back tonight.