Manchester United set to step up chase for Alex Sandro but face competition from Chelsea

He's a player in demand.

There is a scarcity of top full-backs in modern football. That's probably why Benjamin Mendy and Kyle Walker cost Manchester City £50m each; supply and demand and all that. On that nite, it's no surprise that Manchester United have joined the race to sign Juventus left-back Alex Sandro, according to reports in The Mirror. The 26-year-old joined Juventus from Porto in 2015 for €26m and has since doubled his value over the course of two and a half seasons. The left side of defence has been an issue for United since Luke Shaw struggled to settle in and then broke his leg just as he was hitting form. Several players including Marcos Rojo, Ashley Young and Daley Blind have played in the position over the past couple of seasons but Shaw has broken back into the team this season. The 22-year-old has put together a series of impressive performances of late, earning himself a one-year contract extension, but it seems that is a short-term fix to a long-term problem. José Mourinho has identified Alex Sandro as the solution to that problem and asked the United board to meet Juventus' £53m asking price for the Brazilian. Chelsea's interest in the player has been well documented, but the hefty fee necessary to take him away from the Italian champions has been an obstacle. Should Sandro end up at Old Trafford, United could end up with an entirely new, very expensive left side this window. Mourinho will have to eat a slice of humble pie if United sign Sandro for that price after his comments criticising City for "signing a full-back for the price of a striker."