Trusting Grant Williams as a small-ball center

In the NBA, there are teams which you can play drop defense against, and there are teams you can’t. The LA Clippers are most certainly a team you want to avoid playing drop defense against, yet on Monday night, with both Al Horford and Robert Williams ruled out, that’s exactly what the Boston Celtics were forced to do.

Blake Griffin and Luke Kornet are both serviceable big men, capable of making an impact on the boards, creating space via screens, and hitting their open jumpers — but they are not mobile big men, thus forcing you to incorporate a drop system to keep them on the court. The problem with playing drop is that it generates a ton of mid-range space, and more importantly, it muddies your switching principles, making it far easier to chase a ball-handler rather than switch out onto a screener that has ‘popped’ around the perimeter.

That’s where Grant Williams comes in.

Williams is a versatile defender with solid lateral quickness and under-appreciated strength. The fourth-year forward is big enough to absorb contact on the block but quick enough to close out onto shooters around the perimeter to impact their shot. And most importantly, his ability to guard up and down multiple positions ensures the Celtics can run their primary switching system when he’s on the floor.

For a stretch of time in the third quarter against the Clippers, we got to see how the Celtics would look with Williams manning the middle, and the results were encouraging, as Boston looked to be a faster unit on both sides of the ball.

If we look at the above possession, we can quickly see how Boston’s defense appears to be increasingly versatile. Williams is guarding out on the perimeter, we see multiple switches take place, and Boston is making it difficult to beat their point-of-attack defense. Jaylen Brown is doing an excellent job of fronting Ivica Zubac in the post, while Jayson Tatum is shading over to the weakside block, ready to help if needed.

The possession still ends in a bucket, but that’s irrelevant; after all, the great defense doesn’t always equal a stop, just like awesome offense can often result in a miss. What’s encouraging here is that the Celtics looked ready to get out and run while also staying committed to limiting the Clippers' ability to hurt them off the bounce — something which they struggled to do throughout the contest.

Here, we have the very next possession, and once again, the Celtics seem to be executing at a higher level than when they were covering for a drop defender. Once again, we see some initial switches, with Williams ending up being tasked with guarding Kawhi Leonard before another switch puts him onto Nic Batum.

Suddenly, the Celtics are able to collapse on drives and X-out to shooters on contests, and things look to be increasingly robust on that end of the floor.

Ok, I get it; Williams isn’t the ideal guy to be manning the middle for long stretches due to the size he gives up and the negative impact that can have on the boards. Yet, with your two best bigs sitting out, surely his presence is far more beneficial than sticking a drop big against one of the deeper wing-scoring teams in the league, a team that also boasts multiple guards who can penetrate off the dribble and pull-up from pretty much anywhere.

Offensively speaking, Williams’ presence as the center still makes sense. Capable of operating as the big man in delay sets, a solid screener, and with a newfound ability to bully drive his way into the post or attack close-outs by dropping his shoulder, Williams is perfectly suited to fulfilling Horford’s duties at the 5.

One of the biggest differences between Horford and Kornet/Griffin is that he’s still incredibly versatile on the offensive end and can give you options as a screener, popper, driver, and post-player. When operating with one of Griffin or Kornet, Boston’s options become limited, as they have to play to their big man's strengths if they want to keep the flow of their offense trending in the right direction.

However, without a versatile center floating around the court, it’s easy for the Celtics' offense to bog down and become over-reliant on screening actions to generate their offense — not good screening actions either, more like single-screen, drive and reset actions.

“You know, it kinda reminded me a little bit of last year; we got a little stagnated, we didn’t do our job…We have to get back to who we are, playing the way we wanna play, and having fun out there…We know how much talent we have, and we know the capabilities of this team. But in order for us to really take a leap and be special, be great, we have to, even when things aren’t going our way, we did that the first 12, 10 games of the season, but we have to do a good job of staying honed in on what we want to accomplish,” Williams said during his post-game press conference.

Williams is most likely not the long-term answer as Boston’s center, but on nights like Monday night, when your options are limited and drop coverage is simply inviting your opponent to cook you off the dribble and attack the space behind your perimeter defense, playing him at the 5 could be your best option.

After all, Williams has been learning from Horford for the past 18 months, and on the basis of the small sample size we’ve seen from him at the 5, it looks like he’s capable of holding his own against the bigger bodies in the NBA. Luckily, the Los Angeles Lakers, Boston’s next opponent, is one of the teams where drop defense actually makes sense, so Williams won’t be asked to play up a position.

Still, the option is there, Joe Mazzulla just has to be bold enough to utilize it from the jump rather than spot minutes midway through the third quarter when the team is already trailing.