A coated golf ball includes a single or dual core and a cover layer formed from a thermoplastic polyurethane (TPU). The TPU cover preferably has a first polyurethane coating layer and a second polyurethane coating layer disposed about the first polyurethane coating layer. In a preferred embodiment, he first polyurethane coating layer includes unreacted isocyanate groups and has an isocyanate index of at least about 120. Preferably, the first polyurethane coating layer has an isocyanate index of at least about 150, more preferably, at least about 200, and most preferably at least about 250.