According to the Guardian, the lack of progress on the transfer front has greatly frustrated the 47-year-old as rumours have grown of a fall out with the club's hierarchy.
The Italian reports back to first-team training in the first week of July and Chelsea hope to have two new signings waiting for him when he returns.
The Brazilian is wanted by the Blues to strengthen their left wing-back position and reports on Saturday suggested they had made a £55m bid for his services.
Sandro, who has been away on worldwide duty with Brazil, is on around £75,000-a-week at Juventus, a figure Chelsea can easily improve on, and the defender has been told his club will not stand in his way if he makes it clear he wants to go.
"Players are always their own boss". "But I don't know what he [Sandro] thinks about the interest", Marotta said.
The Brazilian ace was a key part of the Bianconeri's success last season, as they won a domestic double while also reaching the Champions League final.
Willy Caballero, who will leave Manchester City under freedom of contract at the end of the month, is to join on a free transfer to serve as the back-up goalkeeper to Thibaut Courtois following Asmir Begovic's sale to Bournemouth.