The pair are currently sidelined due to injuries but appeared to be keeping themselves in a positive mood as their team-mates prepare for their crunch Premier League clash with United.
Neither Aguero nor Silva featured as City secured a dramatic late 2-1 win over Sevilla in the Champions League on Wednesday night.
But the pair are working hard on their fitness in a bid to return to action as soon as possible.
Aguero posted the picture above on his personal Instagram account and wrote: “At the gym, starting my recovery work out with the great David Silva.”
Aguero is expected to be out of action for around a month after the striker was carried off with a leg injury during Argentina’s World Cup qualifier against Ecuador.
City head into Sunday’s game top of the Premier League table and two points ahead of both Arsenal and Manchester United.
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