Wayne Rooney's surprise return to English football as a player-coach at Derby will shift attention to his post-playing future but the former England captain insists he still has plenty to offer on the pitch first.

Rooney will cut short his 18-month American adventure with DC United at the end of the MLS season to join Derby in January 2020.

The 33-year-old's player-coach status will allow him to build his credentials as a future manager under the tutelage of Phillip Cocu, but Rooney believes he can help fire the Rams into the Premier League on the pitch too.

But asked for the best bit of advice he had received, he singled out something he hopes can lead him to further success both as a player and beyond.

"I always remember Sir Alex Ferguson saying, the hardest thing to do in life is to work hard," he said. "I think it's true, no matter what you do. Whether it's on football or you've got a day job in an office, the most difficult thing to do is to stay motivated and to work hard.

"If you can do that it's a great quality to have."