Sand
As the sand infill becomes increasingly compacted and a certain level of solidification becomes evident, the performance of the court will rapidly deteriorate. Initially, the court may appear to be playing better as it appears to be more solid, giving a truer bounce, but as the surface will continue to harden and will become less reliable.
Another problem will be experienced with footing becoming treacherous. The sand build up and subsequent hardening in the pile of the artificial grass allows less traction and so slipping is more common, the court becomes faster than normal and more difficult to play.
On average, a standard size court requires approximately 1-2 tonne of sand to bring the court back to recommended levels.