United were beaten 1-0 by Bayern Munich at the Allianz Arena, five days before their Premier League campaign begins at home to Leicester.
Manager Mourinho, without some key players due to their involvement at the World Cup, including Paul Pogba, Romelu Lukaku and Jesse Lingard, brought on academy prospects James Garner, Axel Tuanzebe, Tahith Chong and Demetri Mitchell during the second half.
At full-time, the Portuguese compared his youthful team to the raft of talent at Bayern’s disposal, including experienced players such as Robert Lewandowski and Arjen Robben.
“Finally, it’s over. Finally, such a difficult pre-season is over,” Mourinho told manutd.com.
“The players were, once more, brilliant. They could not have done better than what they did. (It was a) fantastic experience for the boys.
“There was a moment I was looking to the area and there was Axel at centre-back to left, Demetri at left wing-back, Garner in midfield on the left and Chong.
“At the same time it was Lewandowski on Axel, Robben on Mitchell, (Leon) Goretzka on Garner and (Niklas) Sule on Chong.
“It was fantastic, absolutely fantastic. We were playing against their best team, it was their complete squad apart from (Corentin) Tolisso.”
— Sport360° (@Sport360) August 6, 2018
Mourinho, who has been linked with moves for Tottenham defender Toby Alderweireld and Leicester centre-back Harry Maguire before Thursday’s transfer window, selected Alexis Sanchez as captain in Bavaria.
Reports in Germany on Sunday claimed United have also expressed an interest in Bayern defender Jerome Boateng.
Forward Marcus Rashford donned the number 10 shirt, with the club later confirming he would keep the squad number, previously worn by Zlatan Ibrahimovic and Wayne Rooney, for the coming season.
“Yeah, he wanted it. He always wanted it,” Mourinho said of Rashford’s switch from 19 to 10.
“Of course, he respected the big Rooney and then Zlatan wanted to have it.
“He was in the shadow, waiting for the opportunity and now the shirt is empty. It’s something fantastic for the kid, let’s give the shirt to him.”
Javi Martinez scored the only goal of the game, heading home from a second-half corner.
Pep Guardiola was proud of Manchester City‘s effort in a Community Shield victory that left Maurizio Sarri under no illusion about the task ahead of him at Chelsea.
Guardiola plumped for a surprisingly strong side in the Sunday sun at Wembley, where Aguero was among six of City’s World Cup stars in the starting line-up.
4 - Manchester City's final league positions in the four previous campaigns they've won the Community Shield:— OptaJoe (@OptaJoe) August 5, 2018
1937-38 - 21st
1968-69 - 13th
1972-73 - 11th
2012-13 - 2nd
What they lacked in sharpness they more than made up for in quality against a Chelsea side struggling for coherence under new boss Sarri.
“Kyle Walker trained just two training sessions,” Guardiola said. “It’s complicated for all of them but they are such competitive guys.
“They are my pride. Hats off (to them) because it is not easy to play with such a short time (to prepare).
“We worked just four or five days thinking about the final. We prepared for the final.
“We knew a little bit from Napoli last season what Maurizio could do. We saw the games against Perth, Inter and Arsenal and we tried to figure out what we can do with and without the ball.
“We would like to be more intense in the pressing, but it was impossible because the players were absolutely exhausted. In the second half they felt a little bit comfortable.
“Of course, winning 2-0, it was easier. In general, we made a good, good performance.
“I didn’t expect that level in that period after a short, short training session, like from Fernandinho, Sergio – most of them.
“I appreciate – thank you so much – the players who came back earlier, like Bernardo (Silva), like Vinny (Kompany).
“Bernardo Silva played an incredible performance today. I am so satisfied.
“It’s a minor title, everybody is going for the Premier League, the FA Cup or the Champions League. But to play for this title you have to win the Premier League or the FA up so to play this competition is not easy.
“Once we are there we just try to be serious, to play strong in the head. We did it and that is why we are satisfied.
“We are still far away from the physical condition we want to play. In most cases still we are far, far away.
“The players are in bad, bad condition and hopefully this week we have seven days and the next week seven days more where we can increase our level.”
Guardiola heaped praise on man-of-the-match Aguero after his match-winning brace and Silva for a “masterpiece” of a performance that ensures he is the first name on the team sheet against Arsenal.
While City tweak ahead of their Premier League opener, Sarri has major work to do.
Just three weeks into the job, the Italian is left facing an uphill battle to prepare and shape his squad for Saturday’s match against Huddersfield and beyond.
“In this moment, there is a little difference – maybe not little – between us and City,” Sarri said.
“About the performance, I think in the first half it was not too bad.
“In the second half there was a big difference from the physical point of view, I think, so we have to work.
“Our pre-season until now has been a bit crazy I think and so we have to work.”
Sarri has still not seen six of his players, compounding issues in getting across his philosophy.
“We have the idea to press,” the Italian added. “Sometimes we press in the right way but sometimes not.
“We have the idea to be in control of the match but today we were not in control of the match.
“So, I think it’s a long way we have to work. It’s not very easy.
“In the next week we have a friendly match again (against Lyon) and I prefer in this moment to stay on the pitch with the players only for training.”
The 26-year-old has been number one at Stamford Bridge ever since returning from an extended loan spell at Atletico Madrid in 2014.
Courtois’ desire to return to Spain is well-documented, with the goalkeeper’s agent Christophe Henrotay having publicly pleaded with Chelsea to allow him to leave for Madrid this summer.
Real Madrid have been strongly linked with the Belgium international for years and recently-appointed Blues boss Sarri is willing to sell him if that is what the player requests.
“I have no reaction on the agent,” the Chelsea boss said with a laugh after the 2-0 defeat to Manchester City in the Community Shield.
“I am not interested in the agent. I want to hear Courtois.
“If Courtois tomorrow will tell me the same, I have to speak with my club of course because I want only players with a very high level of motivation.
“I don’t have anything to answer to the agent.”