The Brazil international was the Red Devils’ marquee signing in the 2018 summer transfer window after Fred completed a £52m deal from Ukrainian club Shakhtar Donetsk.
Manchester United won the race to sign Fred after the South American playmaker was previously linked with a move to reigning Premier League champions Manchester City.
Fred arrived at Old Trafford with a rich pedigree after the 25-year-old scored 14 goals in 156 appearances for Shakhtar Donetsk between 2013 and 2018.
However, the summer signing has started six of Manchester United’s 12 games in the Premier League, making a further appearance from the bench.
He started Manchester United’s 2-1 win at Bournemouth last month but Fred was substituted in the 56th minute with the scoreline at 1-1.
Some Red Devils supporters have criticised Mourinho’s reluctance to give the Brazilian playmaker a regular starting spot given the lack of invention in the Manchester United team.
However, club legend Irwin believes the Manchester United manager is attempting to give Fred time to adapt to Premier League football.
“The manager, like he did with [Victor] Lindelof, he is letting Fred settle and get used to the pace of the Premier League,” Irwin told MUTV, as quoted by Metro.
“He came across from Shakhtar and I can’t imagine the pace across there is anywhere near our league.”
Irwin added: “I think you’ll see the best of Fred in the coming few months. He is aggressive, runs around and is energetic.
“I think we’ll see more of Fred, I really do.”
Victor Lindelof was signed in a £30m deal from Benfica in the 2017 summer transfer window but the Sweden international started just 13 Premier League games last season.
However, the Manchester United centre-half has established himself as an automatic starter in the current campaign.
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