When the Boston Celtics signed veteran big man Tristan Thompson last week, most of the coverage focused on the way he would address their lack of size and how he could improve their defense. And, for good reason. Thompson gives the Celtics another big body down low to deal with the bulkier centers in the league, and he's a versatile defender who can protect the rim but won't be made a fool by smaller players on the perimeter. 

Yet Thompson's impact won't be limited to what he does on the defensive side of the floor. Is he a guy you can throw the ball to in the post and expect that he'll get you a bucket? No. Nor, despite his flirtations with the 3-point line last season, is he going to be a serious threat to space the floor. Still, even if it won't be in the most obvious ways, he'll boost the Celtics' offense around the margins. 

For one, he's an elite offensive rebounder, pulling down four per game last season which was second in the league. That ability to create extra opportunities will be a welcome addition to a Celtics team that finished in the middle of the pack last season in second-chance points -- tied for 12th at 13.3 per game. 

Perhaps the biggest reason to be excited about Thompson's arrival, however, is his screening ability. Yeah, that's right, we're going to get extremely nerdy and talk about the importance of screen-setting today. Thompson is one of the best screeners in the league, and the Celtics' guards and wings should reap the benefits of his prowess in this area. 

Consider that since the league started tracking screen assists four seasons ago, Thompson has been in the top 10 three times; the Celtics ran pick-and-roll on over one-third of their possessions last season. Of the top 13 most efficient pick-and-roll scorers last season (minimum 150 possessions), four are now in Boston -- Kemba Walker, Jeff Teague, Jayson Tatum and Marcus Smart. As far as niche skillset matches go, it doesn't get much better than Thompson and the Celtics. 

Let's take a closer look at just how the big man will help make life easier for his new teammates. 

First and foremost, we'll start with the basics. One of the main reasons Thompson is such an effective screener is that he establishes an extremely wide base. It's actually easier to see this with screenshots rather than video, just to get an idea. 


Thompson is already a big guy, but look at how much more space he takes up just by spreading his feet out further than shoulder-width apart. 


Not only is he tough to knock off balance like this, but he makes defenders go even further out of their way to chase their man. So much of success in the NBA is creating small advantages, and a defender needing an extra step to get around Thompson can make the difference between a pull-up jumper being clean or contested. 

He's not just about strength and size, though. Thompson also has nimble feet for a big man and uses his athleticism well in the screening game. In particular, he's adept at switching the angle of his screens at a moment's notice, which can make life extremely difficult for defenders. 

Watch here how he comes down the floor as if he's going to set a screen on the inside. While Darius Garland fakes that way, Thompson quickly flips the pick to the outside, so that when Garland spins back, Thompson is able to wipe out his defender and create an open look. (Thompson actually ends up crashing the glass here for an easy put-back, thus showing off his offensive rebounding on the same play.)

Here's another example that shows how well he can react and adjust to what the guard is doing. At first, he sets up so that Collin Sexton could come off the screen and get downhill to the basket. Sexton takes one dribble that way, then crosses over, and Thompson immediately jumps back to the other side and gets him a wide-open jumper. 

This one is a little more subtle, but just as effective. As Sexton drives, Thompson hits Paul Millsap with the screen, then ever so slightly shifts the angle of his body to keep Millsap on the outside, which creates a wide-open jumper for Sexton. 

Kemba Walker, in particular, should feast off this kind of screening action from Thompson. In fact, we don't even have to imagine how. Just look at how he sets up the defense and takes advantage of Daniel Theis using the same tactic. Walker is already too shifty for most defenders to stick with as he navigates off high ball-screens, and Thompson is going to make things even easier for him. 

Along with his size and athleticism, Thompson's experience and understanding of the game are what make him such a complete screener. We saw it in the way he can change the angle to create more space for the ball-handler, but it's also evident in some of the little tricks he uses -- ones that may or may not be legal. 

Remember how he makes himself big with such a wide base? Look at this little move where he makes sure to get his feet on the outside of Dillon Brooks' feet. It doesn't actually lead to anything, but in addition to being funny, it shows what sort of level he's thinking at.

Another savvy little maneuver he likes to use is related to how he reads the game and changes the angle of his screens. When defenders go under on the perimeter, he'll ever so slightly just turn and back up into them to keep them on the wrong side. Jayson Tatum, with his burgeoning pull-up 3 ability, will love this. So too will Marcus Smart, who has quietly become a dangerous shooter off the dribble, and is never shy about letting it fly. 

In this instance, Thompson shows off another bit of craftsmanship. After setting a high ball screen, he rolls to the rim, then sets another screen on the big to wall him off and open up a path to the rim. If he gets into the gym and starts picking up Daniel Theis' signature seal move, the Celtics will really be in business. 

None of these things are going to show up in box scores, or be what gets discussed after games. But what will be talked about is winning, and Thompson's dirty work will help the Celtics do that.