United confirmed on Saturday morning they had agreed a fee with Ajax for the versatile 24-year-old.
Blind is expected to fly to Manchester to agree personal terms and undergo a medical before Monday's 11pm transfer deadline.
Van Gaal, who has already signed four players this summer, said after the 0-0 draw at Burnley: "He'll come to Manchester to have a medical, and then we might have a new player."
The deal to bring Blind to Old Trafford is thought to be worth around £14million.
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