The Red Devils signed the Serbia international in a £40m deal from defending Premier League champions Chelsea FC last summer.
The title holders’ raised eyebrows with their decision to sell a key part of their title-winning team to a direct Premier League rival.
The Manchester United summer signing helped to reinforce Jose Mourinho’s midfield for the 2017-18 campaign.
While club record signing Paul Pogba has struggled in the middle of the park, Matic has generally excelled in a holding role.
Former Chelsea FC winger Nevin claimed that Matic has now become Manchester United’s most important player.
“I am beginning to think Matic is their most important player the more I watch them now,” Nevin told Irish radio station Newstalk.
“He is killing everything in that area. He keeps on sitting there and he keeps on doing his job.”
Manchester United were 2-1 winners against bitter rivals Liverpool FC in the Premier League at Anfield on Saturday evening.
The Red Devils lost 2-1 to Sevilla in the second leg of their Champions League last-16 clash on Tuesday night.
Manchester United won the Europa League and the League Cup last season to enjoy a winning start under Mouirnho.
The Red Devils made a return to winning ways with a 2-0 victory over Brighton in the FA Cup quarter-final on Saturday as Matic netted one and set up the other.
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