Having re-signed for the Blues while Mourinho was still at the helm, the 29-year-old became a pivotal player as Chelsea won their 4th Premier League title in 2014. Matic has intelligence and experience of the Premier League.
With Matic now in a United shirt, it is unlikely Fabinho would be used to screen the defence, but his knowledge at right-back would be welcomed by the self-proclaimed Special One. While Conte wanted him to stay, the story of owner Roman Abramovich stepping in and sanctioning the move himself, like he did with Petr Cech and Arsenal, is the best example of why this move happened even though the manager had other plans.
Matic made a decision to call time on his second spell at Stamford Bridge after Chelsea emerged victorious in their chase of ex-Monaco man Tiemoue Bakayoko.
Conte stated: "Matic knows very well what I think about him - the importance for me about this player, who is a really good player, a top player, very important for our team".
No new Chelsea signing is under more pressure than Alvaro Morata, brought in for a club-record initial fee of £58m from Real Madrid to replace the unsettled Diego Costa as the focal point of Conte's attack. We are the most physical league.
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Lighthizer, a respected negotiator who helped implement some of the most protectionist trade policies of recent decades during the Reagan administration.
He added: "We can do that but we can also play with four at the back. He's working very well and starting to understand or idea of football".
The former Red Devils midfielder told Paddy Power: "Some people have said that they can't believe Chelsea let Matic go to United, and that they've handed them the title, but I don't see that".
"You saw that with Chelsea last year - him and Kante were magnificent last year and that allowed Hazard, Fabregas, whoever else was playing that bit of freedom, and I'm hoping he'll do that for United - a bit of freedom for Pogba, Martial, Lingard, Mkhitaryan - these players really need to step up this year".
"They've been very successful over the past 10 to 15 years, so I think you have to have faith in that". All of a sudden United are in the driving seat ahead of Chelsea to win the Premier League. You have to have faith in the manager.