A 2-1 victory on Friday night, built around a stirring performance and an early penalty from World Cup victor Pogba as well as Luke Shaw's first career goal, might have been cause for good cheer but Mourinho chose the occasion to revisit his concerns over the club's recent business.
"Of course it makes me proud, it makes me happy to wear this (armband) at a big club like Manchester United", he said.
"It's the best feeling I have had in my career".
And after a brief conversation with Sanchez, Pogba stepped up to bury the spot kick - but only after an unusual run-up that became an instant hit on Twitter.
Pogba's focus on trust seemed pointed, as did his post on Twitter shortly after the match.
"It was not easy to manage the game from the touchline, but I told the players we had good periods, lots of glimpses of the type of football we wanted to play".
Their first thought when they got the ball was always to get it forward and they were trying to get their wide players high up the pitch, which is the United way.
Emergency declared head of Charlottesville anniversary
And critics said their delayed response contributed to clashes between white supremacists and neo-Nazis and counterprotesters . Ralph Northam declared a state of emergency for the state, authorizing the Virginia National Guard to help keep the peace.
"That's football management. I think football is changing and managers should be called head coaches".
Read the key comments from the boss as he spoke to Sky Sports as well as reporters in his press conference.... We played very well, the performance was okay.
"We knew we were not going to be fit, 100 per cent, but the most important (thing) was to start well the Premier League". His initial shot was stunningly stopped by the Leicester keeper, but the deflection flew into the air and all of Old Trafford held their breaths as they waited to see if it would fall into the back of the net.
Substitute Jamie Vardy pulled one back with a stoppage-time header after Ricardo Pereira's cross came back off the post, but it was too little, too late for Leicester.
Mourinho had aired his grievances over United's lack of transfer activity on a disastrous preseason tour, and again in the pre-match press conference on Thursday.
"So, it's pretty early to speak about this now", Pogba said when asked of their chances of success this term.
It was vital that the Red Devils got their campaign off to a solid start in light of the negativity that has surrounded the club this summer, though Jose Mourinho must shoulder some responsibility for it.
Manchester United: release the creative stars against smaller sides 15. "Even if I forget the goal, it was a complete performance", said Mourinho of the left-back's display.