That's the verdict of Jose Mourinho in the wake of the Red Devils' 4-0 hammering of Premier League strugglers Crystal Palace.
Fellaini started against Roy Hodgson's Eagles on Saturday afternoon having missed the Champions League trip to CSKA Moscow through injury.
But the 29-year-old midfielder showed no signs of any niggling issues as he turned in another high quality performance for Mourinho's side.
Fellaini scored twice as United went ahead of rivals Manchester City on points, albeit temporarily, at the top of the table.
And Mourinho was keen to praise the Belgian, who's experienced his fare share of flak during his four-year spell at Old Trafford.
Mourinho said: "He is a great player and character and we have a good relationship. A strong character who resists the difficulties here.
"Some people did not recognise his qualities so he has to be a strong character. He is a fighter.
"I am really pleased that I help him reach this level and to change the perception that the fans have now. I am really happy for him.
"Fellaini has important qualities and I try and use his qualities depending on the situations. He plays with me as a defensive midfielder and as a second striker and adapts to the needs of the team."
Fellaini will be hoping to impress once again when United visit Liverpool in the Premier League on Saturday October 14.
He's on international duty with Belgium for the next fortnight.
