Jose Mourinho's "200 per cent" faith in Marouane Fellaini means the Manchester United midfielder is desperate to repay his manager.
Fellaini was not expected to play a key role under the incoming United manager, but has started all three Premier League matches to date, even after the signing of Paul Pogba from Juventus for a world-record transfer fee.
The Belgium international said that while he featured heavily under Mourinho's predecessor Louis van Gaal, he appreciates the Portuguese boss playing him in a defensive midfield role.
"Louis van Gaal trusted me, I played a lot of games," Fellaini told Sky Sports ahead of Saturday's blockbuster derby against Manchester City.
"This season, though, I'm playing in my position and I feel the trust of the manager.
"He has given me confidence and I will give everything. [Mourinho's faith] has had a big impact on me because when someone trusts you 200 per cent you have to repay that. The manager knows my qualities, he knows what I can do.
"He spoke to me on the first day when I arrived back from holiday and I have worked hard like I do every time.
"I don't need to explain myself, all the managers I've had know my quality. I'm here today and I'm trying hard like I always do to give my best on the pitch."
Fellaini is looking forward to the special atmosphere of a derby at Old Trafford, although he is expecting Pep Guardiola's City to put up a strong challenge.
"Everyone wants to play these games," Fellaini said. "It's a big game, a derby and everyone in the world will watch this game so it is an important game for both teams.
"When you play against Liverpool and City the tension is there but I think it is very big this season because there are new managers and players.
"A lot of players have come to this country this season, as too have a lot of great managers so this season it's special.
"There will be a lot of challenges, the crowd will be behind us so it will be a good game."