The Daily Record's Duncan Castles reported left-back is the Red Devils' top problem area ahead of January, and manager Jose Mourinho has been given a budget of around €90 million (£78.5 million) to address his squad's issues.
Matt Law of the Telegraph previously noted Juventus value Sandro in the region of £50 million, and the former FC Porto man is pushing for a move despite committing his future to the club during the summer. The report added Chelsea are still interested after missing out earlier in 2017.
Spanish gossip website Fichajes (h/t Football Espana) also got in on the fun, reporting the Bianconeri have already started the search for a replacement, with Valencia's Jose Gaya said to be their main target.
Castles' article also said Juventus will not sell in January unless the offer is too good to pass up, and Mourinho will listen to bids for Luke Shaw and Matteo Darmian in order to make room for the Brazilian.
The relationship between Mourinho and Castles has been well-established―he didn't hide he was among his contacts in an interview with Media Matters (h/t Football365)―and some pundits wondered whether this latest report had anything to do with United's chase for Tottenham Hotspur's Danny Rose. Nooruddean Choudry was one of them:
Sandro would make a lot of sense as a target for United, however, perhaps even more than Rose. The 26-year-old is widely regarded as one of the world's best two-way full-backs, standing out for both his attacking contributions and defensive abilities.
He was sensational for Juventus last season, regularly overshadowing compatriot Dani Alves, who often played as the right-back. Add to that Sandro's experience in a variety of systems―Juventus aren't afraid to shake things up―and he becomes even more appealing as a midseason addition who can slot in right away.
It's worth noting Sandro's 2017-18 season has been a disappointing one, though. He's been benched in favour of Kwadwo Asamoah on multiple occasions and drawn the ire of fans and pundits alike.
Sportswriter Adam Digby was almost shocked when he assisted Juan Cuadrado in Juventus' 2-0 win over Olympiakos:
Despite his poor form, the Bianconeri will likely hold out for a significant fee, especially if they can pit United and Chelsea against each other in a bidding war.
The Italian champions have an excellent replacement in Leonardo Spinazzola, but the Italy international is on loan at Atalanta, and he and Mattia Caldara won't return until the summer.
A summer transfer still seems more likely unless Mourinho is willing to spend a good chunk of that €90 million on Sandro.