Those at San Siro have been heavily linked with several strikers this summer as they seek to find added spark in the final third of the field.
That search has led them in the direction of Stamford Bridge, with Morata seeing his future called into question after a difficult debut campaign in England and subsequent World Cup snub.
The Spain international is considered to be a sensible target for Milan, given that he has previously impressed with Juventus, and is seen as a better fit than Real Madrid forward Benzema.
Former Rossoneri defender Antonini told RMC Sport on the striker search: "I think that Morata and Milan have already chosen.
"There is clearly a need to convince Chelsea, who hold the cards.
"As far as I'm concerned, for Milan I see the Spaniard as being more suitable than a player like Benzema.
"The Frenchman is the ideal profile for Napoli."
Chelsea invested a club record €64 million (£58m/$77m) in Morata when signing him from Real Madrid in the summer of 2017.
He did offer glimpses of what he is capable of during a difficult season for all concerned at Stamford Bridge, with 15 goals recorded across all competitions.
The arrival of Olivier Giroud in January did, however, nudge him down the pecking order and Maurizio Sarri has now inherited the managerial reins in west London from Antonio Conte.
He is looking to put his own stamp on the Blues squad, with Chelsea exploring other attacking options as they leave the exit door open for Morata.