9 questions with Celtics rookie Grant Williams

Rookie Grant Williams reflected on his first day of training camp after practice on Tuesday.Grant Williams stayed up until 3 a.m. in anticipation of his first NBA training camp practice, but the rookie feels good about his first day.

The Celtics held their first official practice of the 2019-20 NBA season on Tuesday at the Auerbach Center, where the forward had his first taste of preseason in a green and gold uniform. After practice, Williams chatted about the day, how his offseason training prepared for him for it, and how he wants to be the “heartbeat” of the team this season.

He’s also an avid gamer, and said games like “Pokemon Go!” keep his “mind engaged” off the court. He might even try…