"I told them at half time my midfield players couldn't play any better than they had been playing".
He also turned his mind quickly to Wednesday's Champions League quarter-final tie with Liverpool, which City trail 3-0 from the first-leg. They have more points than the others, and they gave no chance to the others.
But while he expects City's title rivals to be more competitive, the Spaniard clearly believes there is room for improvement with his team, especially in European competition.
Mourinho revealed he congratulated Guardiola after the game on winning the title, even if it is not yet mathematically confirmed.
With City 16 points ahead of United with seven games remaining, they have one hand and another four fingers on the league title and if this was a month ago, they would be right on the money for the overwhelming favourites tag. Chris Smalling then got the victor to stun City, whose hopes of sealing the Premier League title against their bitter rivals were dashed.
"Pogba looks like he has come back after leaving Manchester United and has not matured, he is inconsistent but I think Mourinho is the ideal manager to make him consistent and mature". City needed to regroup quickly and try to control the game again in order to find a victor in the final 35 minutes, while United looked very comfortable and ready to score on the counter at any moment.
"The only thing I would say is that all the big teams around the world - maybe in the last two years we spent more - on average, over the last five or 10 years, have spent a lot of money".
"You saw us stand up, coming in 2-0 down at City where they've been fantastic all season - we stepped up and won the game. Our team tried to create and attack, that is what we have done all season, we tried to produce all of that quality and goals", Guardiola said.
"It's the first time we've lost two games in a row this season and now we have to recover, try again, come back to basics and win games". We have to be more focused on set pieces. "We pressed a bit higher and we keep the shape to get a good result", he said. At Anfield the problem was that we did not create any chances.