The duo forged a prolific pairing earlier in the season and have scored 49 goals between them already in the current campaign.
Argentina international Aguero, who has 26 goals this term, but has only recently returned from a hamstring injury sustained in the 5-1 thrashing of Tottenham at White Hart Lane in January.
Negredo has looked very much at home in his first season in England, scoring 23 times and proving to be a real handful.
The Spain frontman has not scored in his last six games and has not started a game alongside Aguero since a League Cup win at West Ham in January, when Negredo picked up a shoulder injury.
With both players now fit, City boss Pellegrini is backing the pair to carry on where they left off as City attempt to add more trophies to their cabinet following their League Cup triumph over Sunderland last Sunday.
He said: "In that moment (earlier in the season), it was very productive for the team – and I hope in the future it can be again.
"But in other moments when Sergio was injured, Negredo played very well at that time.
"It's important to have important strikers. Strikers also live from the goals they score. Alvaro will return to his normal performance. He will continue scoring goals."
City face Wigan Athletic at the Etihad Stadium on Sunday in the quarter-finals of the FA Cup - a repeat of last year's final, in which Wigan won 1-0.
