The Red Devils have been heavily linked with a bid to bring the 28-year-old winger to Old Trafford from Inter Milan this summer as Mourinho looks to beef up his attacking options ahead of next season.
However, despite all of the speculation, Manchester United have so far only signed defender Victor Lindelof and striker Romelu Lukaku this summer.
It remains to be seen whether Manchester United will conclude a deal to bring Perisic to Old Trafford before the end of the summer transfer window.
And respected football journalist Marcotti admits that he is not sure about how Perisic could fit in at Old Trafford.
“He’s certainly a very skilful player and when he’s consistent, he’s outstanding,” Marcotti said on ESPN FC.
“He certainly hasn’t always been a consistent player. My concern is, I just look at the players Manchester United have and I wonder how is everybody going to fit together?
“Martial is still there, you’ve got Mkhitaryan, you’ve got Juan Mata and that’s before we get into (Paul) Pogba, (Ander) Herrera, guys like that.
“I don’t know. If Mourinho wants another option that’s fine. He’s certainly busy and he has quality when he’s good.
“The one thing is, you have to be confident that he’s going to be consistent for you because that is a lot of money to pay for a player who used to be young and a prospect and all of a sudden is what, 27, 28 years old now. He isn’t young anymore.”
Manchester United kicked off their pre-season tour of the US with a comfortable 5-2 win over LA Galaxy on Saturday night, with Marcus Rashford bagging a brace.
The Red Devils are preparing for a return to the Champions League next season.
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