Rooney has made 15 appearances for United this season – scoring eight goals – but Moyes is aware that the 28-year-old may need to recuperate given United's hectic schedule.
The striker has struggled with knee and hamstring problems in recent seasons, and as United battle in four competitions, the Scot acknowledged there may be times when he has to sit games out.
"There will be times when we do have to try and look after him," Moyes said. "At the moment he doesn't need it.
"I look for any signs of a dip. If I saw them, I would probably look to do so (leave him out).
"It doesn't need to be just now. A lot of other clubs are playing their players continuously.
"We can rotate but I will wait. If it doesn't come around and I don't need to, I won't do it."
Former United manager Alex Ferguson suggested in his recent autobiography that Rooney was better at maintaining his fitness through playing games and that rest was not good for him, and Moyes agrees.
"He is a boy who continually gets better in the games he plays," he added.
"The point I am making is that I want to keep him playing as well as he is doing.
"If he keeps doing it I don't need to worry."
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