Carsen Edwards didn’t wait long during the Celtics preseason opener to live up to his reputation. The rookie attempted a 3-point shot on the first possession of his NBA career, just 29 seconds into his debut. And it only took that much time because the Celtics were on defense when he first subbed in.



“Of course,” Marcus Smart said recently, “we all know about Carsen.”



The Celtics are fully aware of the college career Edwards put together at Purdue, including his memorable NCAA tournament run this past spring. The guard arrived in Boston with a longer résumé than many of the players drafted before him at No. 33 and a scouting report well known to even casual basketball fans. While defending Edwards, players better stay attached to his body. With a release as quick as his, he doesn’t need much space to get off a clean look.



“It’s crazy,” Smart said. “It’s ridiculous. It’s...