Abstract: The invention relates to a synthetic grass turf assembly for installation on a supporting soil substrate to provide a game playing surface that combines the feel of natural turf with the wear resistance of synthetic turf. The turf assembly includes a pile fabric with a flexible sheet backing and rows of upstanding synthetic ribbons representing grass blades, extending upwardly from an upper surface of the backing. A unique infill layer of multiple distinct graded courses of particulate material is disposed interstitially between the upstanding ribbons upon the upper surface of the backing and of a depth less than the length of the ribbons. A base course is first placed upon the top surface of the backing and consists exclusively of hard sand granules. A middle course of intermixed hard sand and resilient rubber granules with relative weight ratio of 3 to 1 is then placed upon the base course. A top course exclusively of resilient rubber granules is then placed upon the middle course.