Aguero's agent has already refused this week to rule out a move specifically to Chelsea in January, which will be subject to the overturning of their transfer ban.
Seventies idol Cano, 58, believes the 21-year-old will soon get tired of playing for the unsuccessful club.
"Kun (Aguero) is a great footballer," Cano told Spanish newspaper AS.
"There is every chance that he will get tired and leave Atletico.
"Players ultimately have their personal pride. They speak to each other and ask: 'What have you won'. And Aguero will see that he hasn't won anything and will leave."