Rumours have persisted in the blue half of Manchester since the arrival of Pep Guardiola that the City boss does not see eye to eye and there are suggestions that despite an impressive start to the season, those feelings have reared their ugly head again after the striker was injured in a car crash in Amsterdam on his day off.
Reports claimed that Guardiola was willing to sell the clinical forward during the summer, but only if they managed to bring Alexis Sanchez to the club from Arsenal. When that pursuit failed, the plug was pulled on Aguero's move.
With City expected to return for the Chilean in January, AC have relaunched their move for Aguero.
English publication 'The Sun' reports that the fallen giants are willing to part with £80m to bring the 29-year-old to the San Siro.
Aguero has been in fine form so far this season, scoring seven goals in eight games in all competitions.
Milan are on the look out for a top-tier striker, capable of restoring them to their former glory and they were thought to have made a move for Diego Costa before he sealed his return to Atletico Madrid.
It remains to be seen whether City will allow Aguero to leave and if they do what they value him at, though AC are keen to find out.