Smalling has admitted that Moyes has demanded a more aggressive approach from him since succeeding Sir Alex Ferguson at the Old Trafford giants in the summer - and says he has responded to the challenge.
"I don't think my role has changed too much since David Moyes came in," the 24-year-old defender told the Sunday Mirror.
"But the biggest difference is that the manager really likes his defenders to be aggressive. He likes to see you dominate the player you're marking, whether you are a centre-back or full-back. Once you cross the white line, you need to change.
"Being injury-free has helped me get some of my confidence back this season and I really feel part of it all again.
"I feel good at the moment and think I am developing as a player."
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