The versatile 26-year-old joined the Red Devils last summer but only played a bit part role last term, making 28 appearances in all competitions.
The Italy international also acknowledged that competition for first team places at Old Trafford will be strong.
“I think it is good to have a healthy rivalry when
you are part of a great squad,” Darmian said.“You need to be ready whenever the coach gives you a chance. Mourinho is a great manager, his success speaks for itself.
“Personally I will try to be ready in any position that he decides to play me. I want to improve so I can start the new season in the best possible way.”