Pellegrini's position as manager at the Etihad Stadium came under scrutiny during the second half of last season as City surrendered the league title to Chelsea.
Recovering to claim second position behind Chelsea did not quell the speculation, with Bayern Munich boss Pep Guardiola regularly mentioned as a potential replacement.
But, on Friday, it was announced that Pellegrini had put pen to paper on a new two-year deal running until the end of the 2016-17 campaign.
The Chilean knows his chances of seeing out his deal will depend upon their challenge to reclaim the Premier League title, with their chances of getting off to a good start greatly enhanced by the availability of Aguero.
The striker scored 26 times in 33 top-flight appearances last term but, along with attacking midfielders Silva and Samir Nasri, found himself struck down with a sickness bug this week.
Speaking at a pre-match press conference, Pellegrini confirmed that Aguero and Silva have fully recovered, although doubts remain over Nasri.
"Aguero is working at 100 per cent and so is Silva – Nasri is just returning," he said.
Pellegrini had been expected to hold back Aguero, Pablo Zabaleta, Martin Demichelis and Fernandinho from the season opener following their exploits at the Copa America, but last weekend's chastening 4-2 friendly defeat to Stuttgart appears to have forced a rethink.
Raheem Sterling could join Aguero and Silva in a three-man forward line, although the England international's fellow close-season recruit Fabian Delph will miss out due to a hamstring injury.
On Sterling, Pellegrini added: "[He has been] very, very good.
"The media have been talking about the price, but he's an English player, young, with quality, speed and technical ability. He will improve every year playing with the likes of Yaya [Toure], Silva, Kun [Aguero] - they will help him."
Arsenal winger Serge Gnabry joined West Brom on loan on Friday to become Tony Pulis' fourth major close-season signing.
Fellow wideman James McClean could supply the ammunition to Rickie Lambert, who ended a lacklustre spell with hometown club Liverpool and will hope to form a formidable forward partnership with last season's top scorer Saido Berahino.
James Chester will remain in the Premier League having moved to the Hawthorns from relegated Hull City, while fellow defenders Joleon Lescott and Gareth McAuley (calf) are expected to shake off knocks to feature on Monday.
Ben Foster remains on the sidelines with a cruciate knee ligament injury, meaning Boaz Myhill is expected to start in goal for the hosts.
