The lose for United means that City team can not be displace from the top of the table, thereby given Pep Guardiola his first Premier League title in his second years as that Manager of Manchester United team.
José Mourinho said he could "smell" a bad performance coming from Manchester United after the 1-0 defeat by bottom-of-the-table West Bromwich Albion that confirmed Manchester City as Premier League champions and left him questioning his players' attitude.
A stirring comeback against Pep Guardiola's men last weekend prevented United's neighbours from winning the title and Mourinho suggested that dramatic result created complacency in his side.
United delayed City's title celebrations by winning last week's derby at the Etihad Stadium but Mourinho admitted that victory had a hollow feel.
"We're all winners and we want to win and in those games unfortunately we didn't. Premier League Champions 17/18", City tweeted soon after the final whistle when the fifth English top-flight title of its history was assured.
Since leaving Manchester United in the summer of 2015, Jonny Evans has transformed into a reliable option in the defensive department and he has built a formidable defensive partnership with Ahmed Hegazy this season, which reflects his leadership qualities in the defensive third of the pitch.
The Premier League's record points tally of 95, set by Chelsea in 2004-05, is within City's reach if they can take nine from their last fixtures. Manchester United made 17 shots throughout the game, but that number is not doing a good service to what we have seen.
Inevitably, it will be the failures of this City team that will irritate Guardiola and his players, at the same time offering the critics the opportunity to find fault.
I wouldn't be happy if someone says that I won the title because somebody loses a match.
City had registered a 3-1 win over Tottenham Hotspur at Wembley on Saturday.
When the pressure was really on, City delivered, but the same could not be said of their rivals. The defensive department, in particular, might be in need of a reshuffle with the likes Vincent Kompany already into the final stage of his career.
United had to at least draw to keep the title race mathematically alive, but they were stunned at Old Trafford when Jay Rodriguez headed home after the break.
"I saw lots of people [over] the moon because we won against City".