Massimiliano Allegri concedes it is "very difficult" to see Paul Pogba playing for Juventus again having appeared to settle at Manchester United since Jose Mourinho's departure.
Pogba joined Juventus from United as a youngster in 2012 and enjoyed four successful years in Turin, winning a quartet of Serie A titles.
His form at Juve persuaded United to bring him back to Old Trafford in a then-world record deal of £89 million ($117m) in 2016.
Critics have suggested Pogba has been erratic since returning to United, while his relationship with Mourinho was a regular source of controversy, often giving way to speculation about further transfers to the likes of Barcelona, Paris Saint-Germain and Juve.