The 23-year-old is very highly rated in Holland and Genk posted scouts at NAC's game with De Graafschap over the weekend.
Engelaar is a product of Feyenoord's youth system, but he left De Kuip having failed to make the breakthrough and has spent the last three seasons with NAC.
The youngster has already struck eight goals this season and is being touted in the Belgian media as a possible replacement for Wesley Sonck - who is being tipped to move to one of Europe's elite leagues.
