The Red Devils have been tracking the Chile international for much of the summer, with various rumours suggesting that the player himself has agreed a £182,000-per-week contract to switch to Old Trafford.
Juve are understood to have put a deadline of the end of this week in place for a deal to go through, and will be happy to accept a significant cash payment with Nani involved.
The Portuguese winger is a player the Old Lady are thought to have been watching for a while, and they are keen to get him included if they are to lose Vidal.
United may well bow to such demands, with the wide-man unlikely to have any sort of role in Louis van Gaal’s 3-4-1-2 formation.
Vidal is still set to cost close to £40m with Nani included.
However there are a few sticking points, chiefly the United’s man’s contract that he only signed last year guaranteeing him big wages for some time.
Then there is the Juve man’s knee injury, which is reportedly worrying LVG.