Louis van Gaal has warned De Jong to prove his fitness.
The Barcelona midfielder is a crucial piece in Van Gaal’s system but he was sent back to Camp Nou to deal with his hamstring injury.
The former Man United manager has given time to De Jong to prove his fitness but he will find another player to fill his role if he can’t.
Van Gaal said: “I have let go of that dogma [only selecting players that play for their club] for a long time, otherwise I would not have selected Steven Bergwijn, for example.
“Memphis [Depay] and De Jong are two very important players who have left. I have encouraged them: I will keep a place for you for as long as possible, but you have to be fit.
“The fact that the Dutch national team is not a rehabilitation centre certainly applies to the World Cup, but I have to trust that they are fit when they say that.
“Frenkie de Jong is a determining factor. That’s why I look at being complementary to De Jong, but I also see if I can find someone else for it because we have to be prepared. You never know how a hamstring injury will turn out.”
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