The flamboyant Frenchman has been linked with a shock move to Barcelona over the past couple of weeks, with various reports claiming that his agent Mina Raiola is trying to engineer a second departure from Old Trafford for the World Cup victor.
Back in 2016, the 25-year-old completed his move back to Old Trafford for a-then world record fee, but things could have been very different according to one of Barcelona's directors.
However, the report states Pogba is not to the point where he wishes to force a transfer, with three years left on his contract at Manchester United.
But he was dropped for a crucial Champions League tie with Sevilla in February in favour of 21-year-old Scott McTominay and was substituted during disappointing defeats at Tottenham and Newcastle as City ran away with the title.
Reliable Di Marzio revealed that United have rejected the offer from Barcelona for Pogba.
The two frequently clashed last season, arguing over Pogba's best position, while Mourinho put their relationship under further strain with some questionable comments about his midfielder's performances at the World Cup.
Rumours are now circling again, with Catalan newspaper Mundo Deportivo claiming Barcelona submitted a €50m offer for Pogba on Monday.
However, United could rekindle their hopes of signing World Cup star Harry Maguire, with Leicester closing in on two centre-backs late in the window to safeguard themselves against losing their England worldwide.
Earlier this week, there was talk of Manchester United looking at Mina too. United have decent financial stability, so they do not need to sell the World Cup star.
Mourinho is keen to bolster United's attacking options ahead of Thursday's transfer deadline, with Inter Milan's Croatia star Ivan Perisic also reportedly a target.