The 30-year-old Belgium international is know as something of a controversial figure at Old Trafford and he has been criticised for his physical style of play in the past.
Fellaini is now aiming to hold down a regular spot in the Manchester United team this season as he bids to try and help the Red Devils to challenge for the top flight trophy this term.
The former Everton man was in solid form on Saturday as he notched up an assist to help Manchester United to claim a 2-1 win over Watford.
And Crooks feels that Fellaini is poised to hit top form for Manchester United in the coming weeks and months under Jose Mourinho.
Writing in his column for BBC Sport, Crooks said: “Who’d have thought it? Marouane Fellaini starring in a Manchester United shirt.
“When David Moyes bought the player from Everton it was universally felt that he was not in United’s class. Against Watford he looked like the answer to all their problems.
“Playing like this, Fellaini could be for United the player he was for Everton.”
Manchester United are aiming to try and challenge for the title this season after they finished in second place and without a trophy under Jose Mourinho last term.
The Red Devils are now set to switch their attentions back towards Champions League affairs and their home clash against Young Boys in their group stage opener on Wednesday night.
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