The Sun's Warren Haughton reported the Blues are set to snap up the want-away Sandro ahead of United, who had been eyeing him in January as a solution to their problems at left-back, as they are his preferred destination.
The Bianconeri valued Sandro at £80 million in the summer when Chelsea made an approach for him, but his relationship with the club is said to have declined since then. The Blues will try to capitalise and land him with a "significantly lower bid."
Chelsea lack strength in depth at left wing-back, as manager Antonio Conte's only alternatives to Marcos Alonso are to field the right-sided Davide Zappacosta there or move Cesar Azpilicueta there from the back three, where he is perhaps their most reliable performer.
Football.London's Oliver Harbord has been vocal about their need to address the problem in January:
Oliver Harbord @ojharbord
I banged on about it in the summer and I'm going to bang on about it during the January transfer window. Chelsea need another left-back option, Alonso can't do it all himself #cfc https://t.co/MFOdOodV1g2017-11-13 12:22:37
Sandro's form has been a source of disappointment this season, perhaps as a result of his not getting the move he hoped for in the summer.
Manager Max Allegri has not shied away from being critical of the Brazilian, per Bleacher Report's Adam Digby:
Adam Digby @Adz77
"Alex Sandro was instrumental in the first goal in Athens, but he is not the 'real' Alex Sandro. We mustn't lie" – @OfficialAllegri on the out-of-form Brazilian #JuveInter https://t.co/FafRkxhnju2017-12-8 11:18:27
He has nevertheless managed to rack up five assists in all competitions as well as find the net once, which hints at what he can offer even when he's not at his best.
The 26-year-old's form over the previous two seasons since arriving in Turin from Porto have established him as one of the best left-backs in the world. His efforts last year saw him including in FourFourTwo's 100 best players:
FourFourTwo ⚽️ @FourFourTwo
7⃣2⃣ ⚽️ Alex Sandro 👕 Juventus (@juventusfc) 🇧🇷 Brazil Thanks to an outstanding 2016/17 season, Alex Sandro’s name entered the conversation about the world’s finest full-backs #FFT100Best https://t.co/Thauv5C33d2017-12-12 09:50:05
His attacking prowess is evident from his contributions in the final third, but he's also strong defensively and he has the pace and stamina to perform both roles on the left flank throughout 90 minutes.
Sandro's disappointing form could make Juve slightly more open to letting him leave in January, and if Chelsea do manage to land him, they'll hope the move can revitalise him.
If it does, they'll have simultaneously improved their first XI and added some much-needed depth to the squad.