The Belgium international has established himself as an important member of Mourinho’s squad despite previously struggling at Old Trafford.
Fellaini was signed in a £27m deal from Everton in the 2013 summer transfer window and was used as a scapegoat throughout David Moyes’ disastrous reign.
Life at Manchester United didn’t get much better for Fellani under Louis van Gaal as the Belgian midfielder became a figure of derision.
However, Mourinho has managed to utilise Fellaini in tough games on the road in the Premier League and in Europe since taking over from Van Gaal.
Indeed, Fellaini has even scored two goals in the 2017-18 season after finding the net net against Swiss champions Basel and Leicester City.
Former Tottenham Hotspur midfielder Jenas explained how Mourinho has transformed Fellaini into a useful weapon for the Red Devils.
“Fellaini doesn’t seem to get much of a sniff,” Jenas told BBC Radio 5 Live.
“You wonder where her fit in their midfield. You’d put him in fifth place. But somehow Mourinho has created a role for him.
“He is a weapon for Mourinho.”
Manchester United were 4-1 winners against CSKA Moscow in the Champions League on Wednesday night before easing to a 4-0 victory over Crystal Palace at Old Trafford in the Premier League on Saturday afternoon.
The Red Devils finished in sixth place in the table last term.
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