When it comes to the NBA, change is the one constant every team and every player can count on.
When training camp started a year ago, Williams was considered a low-risk, high-reward draft pick who had a lot - A LOT - of growing up to do.
There were missed flights (hence the "Time Lord" nickname), conditioning issues as well as nagging injuries that made him a non-factor.
As the season wore on, he began to show glimpses of the immense potential that at one point had him pegged as a top-10 selection coming into the 2018 draft.
Fast forward to the 107-106 win over Charlotte in the preseason opener, a game in which Williams was in the starting lineup and scored Boston's first points on a lob dunk.
"It was great to be with the first group," Williams told NBC Sports Boston. "That just shows that the coaches, they have a lot of trust in me."
Certainly, more than they had a year ago, which speaks to the 21-year-old's growth and potential.
It's a successful season for Williams if…
…He spends more time than any of Boston's bigs-by-committee in the starting lineup. It sends a clear message that the strengths in Williams' game are on display enough to where coach Brad Stevens thinks it is a necessity for him to start. At 6-foot-11, Williams has an unusual springy-bounce to his game which allows him to block a bunch of shots and alter many others. He only appeared in 32 games in his rookie season, but he was one of just four players in the NBA with more blocked shots than committed fouls. Most of his offensive damage came on lob dunks at the rim, a dynamic that none of Boston's other bigs can bring to the game the way Williams can. That helps explain why he shot 76 percent in the restricted area last season and he'll look to be even more impactful with more minutes available this season.
It's a disappointing season for Williams if…
…Williams gets lost in the playing time shuffle. Despite being in his second season, only Daniel Theis has more experience as a Celtic among Boston's big men. Rebounding, defense and communicating on the floor will collectively dictate how big (or little) a role Williams will have this season for the Celtics. And like most players, a key to Williams' success will also be him managing to stay healthy. The Celtics selected him with the 27th overall pick in 2018, a significant drop for a player many viewed as having top-10 talent. One of the factors in him dropping so far was his health, be it the knee-related injuries, or concerns with his overall conditioning even when healthy. He has had some minor injuries with the Celtics, including most recently a groin injury. But it doesn't appear as if it'll linger, which is good news for Williams and his goal of being a starter this season.
After spending most of the summer in Boston strengthening both his mental and physical game, Williams has the potential to be the Celtics' most improved player this season. He says his weight is down to about 240 pounds, which is around 10 pounds less than he played with last season. Coaches and players have praised his work this summer and the time he has spent in the gym to get better, which is why he is one of the front-runners to start at center this season. He spent most of his rookie season keeping tabs on Aron Baynes and Al Horford, trying to incorporate their strengths into his own game. He'll get that opportunity for sure this season, whether it is with the first group or coming off the bench as a key reserve.
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Celtics Spotlight: Can Robert Williams seize a starting role in Year 2? originally appeared on NBC Sports Boston