Mourinho will have been well aware that City was going to win the title at some point anyway, but the lack of fight from his players will have been cause for concern.
City are 16 points clear of second placed United, who can only take a maximum of 15 points from their remaining matches.
Guardiola has won the League Cup already for City this season but a first Premier League title, to go with the three La Liga titles he won as manager of Barcelona and the three Bundesliga titles he delivered for Bayern Munich, will be particularly satisfying for the Spaniard.
More importantly, though, it means Pep Guardiola's City team can not now be caught at the top of the table, thus handing the Catalan coach his first Premier League crown in just his second year in English football. "Our City. Premier League Champions 17/18".
Mourinho said the there was no continuity or fluidity in the team's play on Sunday, but he said he thought the result was harsh.
"Whatever you read, I know what really happened".
We were masters in complication.
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A figure between 96 and 104 per cent of rainfall indicates a normal monsoon and between 105 and 110 per cent above normal. Forecast suggests maximum probability for normal rainfall and a low probability for deficient rainfall during the season.
United manager Jose Mourinho had long given up hope of winning the title, instead focusing on finishing second.
"Everything is to play for as I've said all along, we're in a relegation battle until we're safe".
Manchester City have won the Premier League crown with five matches to spare, making them the joint-fastest to clinch the title. "With my experience you don't win titles with inconsistency".
"Consistency at every level, not just the performance level, but the mental, the day by day, everything must be consistent until the last day. That doesn't make me feel super happy and in my opinion affected for sure some of the people that was too happy". "Everything was slow. Everyone was one more touch, one more trick, one more flick, one more turn".
Pogba, one of United's underwhelming performers on the day, was taken off by Mourinho after 58 minutes, but his boss has since hinted that he did this because the Frenchman had already been booked.
The rest of the squad was spread out across Europe, and even beyond, on their day off after City's 3-1 win at Tottenham on Saturday night had left the league title agonizingly close.