The Dutchman bagged both goals at Wembley as Manchester United beat Wigan 2-0 to claim the FA Community Shield.
Moyes said: "We have to be aware how we can use Robin and I will endeavour to make sure I do that to the best of my ability.
"He is so important we have got to look after him and we will do that at the right times.
"We have got other centre-forwards. As you know, Wayne wasn't fit and Chicharito (Javier Hernandez) had an injury."
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