The Spurs boss had questioned the legitimacy of Raheem Sterling's injury, with the England forward having pulled out of international duty with the Three Lions.
And Guardiola will no doubt be having more nightmares featuring his old nemesis after his side slumped to another defeat that leaves them 11th in the Premier League.
For the third time in their last four encounters, Mourinho outsmarted the City boss.
While the visitors enjoyed 66% possession at the Tottenham Hotspur Stadium, the north Londoners anticipated exactly where they would target them and were helped by an early goal.
Heung-min Son's strike inside five minutes allowed Spurs to sit back and when out of possession, Tanguy Ndombele joined Harry Kane in pressing City's high defensive line.
Kane is quite possibly the best 'false 10' in the world right now. His partnership with Son has been incredible all season and they were at it again on Saturday, the South Korean operating up front and the England captain dropping in between the lines.
But if you really want a feel for how Guardiola was undone by Mourinho, there's no better place to head than to Youtube account Football Made Simple.
Their video, entitled 'How Mourinho outwitted Guardiola' shows Spurs' positional awareness was far greater and that City's well-intended plans, based on Kevin De Bruyne and Rodri being allowed much greater freedom in midfield, were thwarted.
The full video can be seen below:
Although City seemed to be peppering Tottenham's goal at times, it's explained that they mainly "accumulated many low-quality chances".
Spurs, on the other hand, had much fewer (22 to 4 attempts, to be precise) - but they enjoyed far more "high-quality chances".
There's a school of thought that the Lilywhites simply got lucky - but it's called a Mourinho masterclass for a reason.News Now - Sport News