Manchester United manager Louis van Gaal has warned Memphis Depay that he must adhere to the team policy or risk a shortened career at the club.

The 21-year-old Dutch forward arrived at Old Trafford to much fanfare from PSV Eindhoven in the summer but has failed to live up to lofty expectations in the early stages of his debut season in England.

Depay sat on the bench as the Red Devils defeated Everton 3-0 at Goodison Park on Saturday and will need to follow the lead of assistant manager Ryan Giggs but also show self-motivation if he wants to avoid becoming the next Angel Di Maria or Radamel Falcao who had ill-fated spells at the club last season.

"Ryan has already given advice to him but the player is responsible for his own deeds," said van Gaal.

"You have to give respect to your team philosophy."

The Dutch tactician added: "We have seen that some players cannot adapt to the team philosophy.

"You cannot know in advance before you buy them. You have to wait and see.

"That happened with Angel Di Maria and Falcao."

When quizzed further on Depay, van Gaal said: "Do I still believe in him? Of course.

"The problem with young players is they are not consistent. That you have to learn. We have to give him time."