City’s Brazilian striker – who has led the line in the absence of the injured Sergio Aguero – capped a fine all-round display at Burnley in midweek with two goals.
And the City boss has urged the 22-year-old to maintain his self-belief and confidence ahead of Saturday’s 179th Manchester derby.
“He has to be himself; we need his goals,” declared Guardiola.
“That’s why we could win the last game - so we need him for his goals. He has put this idea in his head that he can do it every game.
READ: When the Goat was fed by Neville...
WATCH: City v United | Top 5 goals
“Confidence has to be here all the time, not because of a good or bad performance, winning games or losing games.
“With the greatest athletes all the time something undeniable is their mentality and how strong they are
“I think that is the key difference, they have to play, they would not be there without it.