Pep Guardiola praised his makeshift team after they were beaten by a late Leicester penalty in the Community Shield.
With many established stars missing through injury or late returns from their summer exertions – and Jack Grealish waiting in the wings – City boss Guardiola named an unfamiliar line-up at Wembley and gave teenagers Sam Edozie and Cole Palmer a chance to impress.
They gave a good account of themselves and went close to scoring through Ilkay Gundogan's free-kick and Riyad Mahrez, who broke clear only to fire wide.
But it was a spot-kick from former City striker Kelechi Iheanacho, after he was brought down by Nathan Ake two minutes from time, that gave Leicester a 1-0 win.
"I would have loved to win the game," said Guardiola, who has lifted the Community Shield twice.
"Congratulations to Leicester for the victory, but the performance was really good. At this stage of the season, and to play the young guys, was excellent.
"With a little bit of luck and with better decisions in the final third we could have scored. But with all the players out, the players who have trained together the last two weeks have been exceptional.
"We were so good. That is the first step to try again and compete this season."
Guardiola does not expect to have anything like a full-strength side when they face Tottenham in the Premier League opener next weekend.
"It happened last season, we arrived late," he added. "Tomorrow seven or eight players arrive back. That's why I guess at the beginning of the season we will try to get results without being at our best.
"We know we will not be at our best but the players will be better next Sunday. That is the process we have to do.
"I saw many good things today. I don't think we played badly and I told the guys how proud I am. But in this business you need to win."
Grealish made his debut as a 65th-minute substitute just two days after his record £100million switch from Aston Villa.
"He was really good," said Guardiola. "Aggressive, going against full-backs, every time he had the ball he had three players around him. Step by step he will find his best."
However it was another sub, Iheanacho, who secured a second Community Shield for Leicester – 50 years to the day after they won their first.
"Both teams are here on merit and wanted to win," said manager Brendan Rodgers.
"We know it's the end of the pre-season and players are still looking for fitness, but in the last few years it's become a prominent trophy and that's the mindset we want to bring to the team and the club.
"The guys showed great spirit, great quality and eventually got the winning goal. We had a great feeling coming here on the back of the FA Cup final and it was a great occasion."