https://www.polygon.com/2017/10/17/16488922/gran-turismo-sport-offline-functionality-saves

Gran Turismo Sport is finally out today, and players are starting to realize just how much the racing game relies on an online connection: A lot, it turns out.

This has been known for a while, in some sense. Developer Polyphony Digital has always pitched Gran Turismo Sport as an online-focused game because of its integration with the International Automobile Federation (FIA). You can earn an FIA-recognized driving license in the game, which means you can obtain a digital license in Gran Turismo Sport that you can use to drive race cars in real life. In addition, the game offers an online championship endorsed by FIA, so it uses cloud saves to maintain the integrity of the esports competition.