Williams' potential isn't in question, but some wonder whether he'll be able to make the most of his talent:
Williams, 20, has spent the last two years emerging as one of the best defensive players in the country. He averaged 10.4 points, 9.2 rebounds and 2.6 blocks per game during his sophomore campaign, helping lead Texas A&M to a Sweet 16 appearance.
The Aggies had not had a first-round pick since 2007.
"He's been an NBA performer, day in and day out," coach Bill Kennedy told reporters at the time. "I'm really proud of him. He came back to finish strong and did something special for this program and university. He gave us everything he had at the end of the year to put us in this position."
Williams' role at the next level will likely be that of a small-ball 5—at least until he can develop some sort of jumper. He doesn't do much outside the restricted area and is mostly going to do his early NBA work on rim runs and offensive rebounds.
His wingspan (7'5.5") and athleticism should allow him to fill a Clint Capela-type role, and he flashed enough ball-handling ability that he should be OK moving the ball around in sets.
“Defense, whether it’s switching or blocking, I feel like that’s my strongest attribute,” Williams said, per Kendra Andrews of the Washington Post. “And it’s just about embracing it—wanting to stop a guard, having fun and guarding them out there. So once you’re comfortable with it you can get it.
When Gordon Hayward returns to the court, Al Horford will likely get pushed to center on a full-time basis after splitting his time between center and power forward this past season.
Williams provides much needed depth behind Horford at the 5, and already having a five-time All-Star at the position means Boston can be patient with Williams' development.
Considering how much head coach Brad Stevens has gotten out of his young squad, the Celtics are a perfect fit for Williams.