If your tennis court is suffering from extensive cracking, Installing fiberglass over the surface is the worst thing you can do to your court, its sure sounds great but unfortunately this application does not work and it will only make your court surface worse. The only cure the repair a court that is largely cracked is to rectify the stone base or drainage & replace the existing asphalt/substrate.
When fiberglass is installed over cracks; the moisture will rise through the crack and will cause the fiberglass to separate from the asphalt/substrate, within a year or two the surface will ripple or simply crack, as shown from the pictures below.
Commonly we advise tennis court owners to leave the cracks alone, unless the cracked area has shifted, and can be hazardous. Esthetically if you fill and patch the cracks without surfacing the entire court, it will look worse since it is impossible to match the existing colour of the court surface.