BOSTON — Grant Williams is a big boy — 6-foot-8, 240 pounds — but everyone that comes in contact with him on a basketball court still seems to come away mesmerized by his strength.


Williams isn’t just strong, he’s NBA strong. During pre-draft workouts with sports science leaders P3, Williams’ strength graded out in the 96th percentile among all NBA players tested (not just rookies, everyone). Watch college highlights and players tend to bounce off Williams and, now, that strength will likely be the key in him being able to joust with NBA giants.

But how exactly did Williams get so strong?

"I ate my Wheaties growing up, my veggies, all that stuff,” Williams deadpans before exploding into laughter. 

More likely it was his dedication to the weight room that gave Williams his sturdy frame. He tips his cap to family genetics and the work ethic that was instilled in him at an early age. Williams oozes humility but his confidence shines through when he’s asked if he believes his strength gives him a chance to hold his own with NBA bigs.

"Oh yeah, I feel like I can bang and hit those guys and be able to stand up at that level,” said Williams. "It’s really about getting the mobility, where I can be able to stand with them."

Williams knows the concerns about how his game will translate at the NBA level. He’s going to have to gravitate more to the perimeter and extend his range because he won’t always be able to overpower guys like he did in college. 

Williams spent the ramp to draft night working at P3 trying to improve his weaknesses. When the strength numbers came back with eye-popping results, as documented by The Athletic, Williams wasn’t all that surprised.

"I kinda joked around about it, I was like, ‘Hey, I gotta be good at something,’” said Williams. "I may not be the most athletic, all this stuff, but there’s gotta be one thing, some type of test that will give me some credit.”

The Celtics coaching staff has already been impressed by more than William’s pure strength.

"He has some of those characteristics [of undersized big men] already as strengths,  mainly communication and high IQ, being in the right place,” said Celtics assistant coach Scott Morrison, who is helming the summer squad. "He’s been the most vocal player we have out there, kind of directing traffic, calling out coverages; Undersized bigs have to be ready to play every kind of coverage defensively, so it’s important to pick that stuff up and communicate with his teammates. 

"The other thing is outside shooting, and that’s something we’ve worked on with him extra since he’s been here, and he’s knocked some down, so that’s good to see.”

Williams looks comfortable as he puts up post-practice 3-pointers. It’s a work in progress but he understands how important it will be at the next level. 

It’s unfair to expect Williams to step in and do the sort of things that Al Horford did, facilitating the offense from the high post and providing sturdy defense on the back line. But the potential is there. And Williams is ready to work to improve his game, especially after seeing how hard veterans like Gordon Hayward are working this summer.

"It’s definitely like I gotta step my game up as a rookie,” said Williams. "You kinda want not only to stand out but kinda separate yourself. So see what [Hayward is] doing, the morning and how hard he is working, and same with Jayson [Tatum], seeing guys like that and how much time they put into the gym, really not only gives you the map to how to be successful but also allows you to see what it takes at this level.”

Williams got a chance this week to meet a lot of Boston’s veterans, including newcomer Kemba Walker, Hayward, Tatum, and Jaylen Brown. An admitted nerd, is Williams ready to challenge Hayward to a gaming duel?

"Oh no, he’s got me on that one,” said Williams. "He’s built so much time on that where he’d beat me in about 10 seconds. One game I could only possibly beat him on is Jump Force, that’s about it. Maybe FIFA. He doesn’t like sports video games.”

The more intriguing competition could come in the weight room. Williams has heard whispers about the loud, wall-rattling workouts that Semi Ojeleye typically engages in.

"I’ve heard he’s strong. I’ve heard him and Guerschon [Yabusele] both are pretty strong guys,” said Williams. "It’s definitely something where I’m really excited to get to the first game, start banging with these guys."

It’s suggested that all these strong young guys on Boston, it might be a demolition derby on the court.

"No doubt,” said Williams with a playful laugh. "It’s going to be like a blood bath.”

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