Januzaj, who netted twice on his first start for the club in the 2-1 victory over Sunderland last week, is out of contract at Old Trafford next summer and will be free to speak to other clubs as early as January.
The situation has evoked memories of Pogba's exit from the Red Devils, as the France international snubbed the opportunity to extend his deal prior to signing for the Italian giants.
Speaking to reporters, Marotta confirmed an interest in the youngster and believes that United's dithering could have cost them yet another star.
"If they fear another case like Pogba's then they are right," the 56-year-old told Tuttosport.
"It's difficult to understand how we can reach a stage eight months prior to the contract expiring without seeing a renewal.
"Januzaj is a player showing big promise. He is a player of great quality."
The Belgium-born winger is eligible to declare for as many as six nations at international level, with England, Serbia, Turkey, Albania and Kosovo all rivalling the country of his birth for his future.