McTominay has spent his entire career with the Red Devils after progressing through the youth ranks at Old Trafford.
However, the Scotland international is set to end his association with Man United and embark on a new adventure with Serie A side Napoli.
Earlier this week, it was reported that Napoli had reached an agreement with Man United to sign McTominay for £25.4m.
McTominay subsequently travelled to Italy to undergo a medical and was greeted by Napoli fans upon his arrival at Naples airport.
McTominay finalises Napoli move
According to journalist Fabrizio Romano, McTominay has completed his move and its just a matter of time before he is unveiled as new Napoli player.
The update claims that the necessary paperwork has been signed by all parties, paving the way for McTominay to join Antonio Conte's squad.
McTominay is now set to leave Man United after contributing 29 goals and eight assists in 255 appearances in all competitions.
The 27-year-old has won two pieces of silverware during his time with the Red Devils, clinching the EFL Cup in 2022-23 and lifting the FA Cup in 2023-24.
Ten Hag provides reason behind McTominay departure
Ten Hag has admitted he would rather keep McTominay at Old Trafford, but the club need to sanction his departure to sign Paris Saint-Germain's Manuel Ugarte and remain within the Premier League's financial rules.
"It's a little bit mixed, I'm very happy for him," Ten Hag told reporters ahead of Sunday's Premier League clash with Liverpool.
"It's also (a good deal) for us, but it is mixed because I wouldn't prefer to lose him because he's Man United in everything.
"He was so important for our team, for Man United, but unfortunately it's the rules. We have to discuss the rules, when you have to sell and obviously homegrown and academy players bring more value, that's not the right thing to do.
"But I think for everyone, for all parts it's a good deal, for Scott he's happy with it, for Napoli a very good player, but also for us."
McTominay could be joined at the Stadio Diego Armando Maradona by Billy Gilmour, who is on the verge of completing a switch from Brighton & Hove Albion.