Louis van Gaal has warned Robin van Persie that he cannot expect to walk straight back into the Manchester United team upon his return from injury.
The Dutch striker, who has not played since suffering a foot injury against Swansea City in February, made his comeback for the club's Under-21s in midweek.
His absence has coincided with United's best form of the season and Van Gaal has suggested that his compatriot has a fight on to regain his starting place.
"He has to train very hard, play in the second team," he told reporters on Friday ahead of United's trip to Everton this weekend.
"He has to show his qualities again. Then I have to compare him with the positions he can play, with the players that play in that position - it is always the same."
Van Persie has scored 10 goals in 26 appearances for the Red Devils in all competitions this term.