The 34-year-old, who retired from professional football last year after being diagnosed with a cardiac arrhythmia, made 389 appearances for City during a trophy-laden 10 year spell.
In that time, he struck up a great partnership with Sterling during the six years they played together.
Last month, after seven years in Manchester, it was announced that the England international would leave the Etihad and join Chelsea in a deal worth a reported £47.5 million.
Sterling has since scored his first goal for Thomas Tuchel's side in a pre-season clash against Udinese, while City fell to a 3-1 Community Shield defeat to Liverpool on the same day.
Following the Blues' defeat at Wembley, club legend Aguero raised an eyebrow over Sterling's departure.
"I don't understand the sale of Sterling, there are times they (City) make strange decisions," Aguero said on his Twitch channel.
"He was too used to Germany," Aguero said. "Haaland thought he was alone, then Van Dijk arrived and said 'welcome to the Premier League'."
Raheem Sterling has often expressed his admiration for Aguero and after the Argentine retired, the winger paid tribute to his former teammate.
“It’s really sad. He probably had a lot of ambitions that he still wanted to reach at 33, so it was sad to see him go out like that," Sterling said. "But then again, he’s healthy and he’s well so that’s the most important thing.”
The England international added: "His finishing was absolutely ridiculous. To see him in a warm-up before a Manchester City game, he was so relaxed, he doesn’t really take things seriously in a warm-up.
"How easy he made some of that finishing look was scary.
“He can look back on his career with the biggest smile because he’s an absolute legend and not just for Manchester City. With Argentina, he’s a player that for many years and years to come, strikers growing up will look up to him.”
Featured Image Credit: Twitch/Alamy
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