Lancaster-born McTominay had been with United for over 20 years – first attending a soccer school at the club aged five – until his summer departure.
It was a mutual decision to leave, for a fee of £25.7m. McTominay wanted a change of scenery, and the Premier League’s Profitability and Sustainability Rules (PSR) meant the deal made sense to United.
He joined Napoli on the same day as Scotland team-mate Billy Gilmour moved from Brighton for £12m.
But the move nearly did not happen. Another midfielder Marco Brescianini was having a medical at Napoli and seemed set to join from Frosinone.
But suddenly the Italy international completed a loan move to Atalanta, with an obligation to buy, and Napoli signed McTominay instead.
Reports vary on how it all unfolded. Some say Brescianini opted for Atalanta, or Napoli pulled out once McTominay became available, while others say Frosinone tried to change the deal.
Whatever happened, it has worked out well for Napoli.