Shinji Kagawa knows he must prove himself to the new manager at Manchester United.

Having been brought in by Sir Alex Ferguson the 24-year-old now has to impress new manager David Moyes.

"I always think that I must play well," he told premierleague.com.

"And I always have an image in my mind of how I want to play, wherever the position.

"Whenever there is a tough time, whenever it gets difficult for me, I just train and look ahead to the future."