Over the first nineteen games of the season, the Celtics averaged a meager 102.9 OffRtg (20th in the NBA). Since their 18-game win streak was snapped in Miami on November 22nd, they’ve been red hot at 115.8 OffRtg. They’re now in the upper half of the league in offense (105.9 OffRtg) and trending up.

There are little things that have helped elevate the Celtics’ offense of late. First, there’s Marcus Smart’s improved shooting. He’s shooting 47.8% from behind the arc over the last six games and has really shown his maturity as a playmaker with 38 total assists. Jayson Tatum and Al Horford have both been 12 for 21 from 3. Marcus Morris has been a consistent scorer, particularly in the second half for the second unit with his inside-outside game.

However, the biggest difference maker has been Boston’s aggressiveness to not just get the defense moving from side to side but also to collapse it into the paint and play inside out. Maybe more important than their attacking style is that the Celtics now have the players to actually take advantage of it.

For what it’s worth, I loved last year’s team. I think their mindset and grittiness laid down the foundation of this rebuild and the Celtics don’t have the players they do now if it wasn’t for the like of Isaiah Thomas, Avery Bradley, Jae Crowder, and Amir Johnson. With that said, they just didn’t have the versatility that the current roster has. How often did we say Crowder attacking close outs? Bradley extended his range, but wouldn’t you rather see a younger, more athletic Jaylen Brown attacking the rim? Amir came to Boston as one of the most efficient roll men in the league, but Father Time robbed him of his footwork and agility. There could be legitimate debate about who’s the better player—Kyrie vs. IT—but after watching Irving’s first 25 games in green, it’s noticeable how little his teammates have to do for him to get a good shot off. His creativity off the dribble opens up the offense in a way that Thomas never did.

First, let’s backtrack a little bit and look at some early film of Boston’s offense. This is a popular action the Celtics ran a lot early in Stevens' tenure. It's a 5-out, delay set that gives every player an opportunity to read and react to the defense. There's a lot of ball movement with players moving side to side and looking for cracks in the D. There are brush screens and dribble hand offs just to get the defense moving, but nothing that really puts it into jeopardy.

Much of this was out of necessity. Isaiah Thomas alone could put pressure on opposing teams, but outside of him, the Celtics lacked versatility and another consistent scorer that could hit the outside shot, drive into the paint, and finish around the rim. Al Horford has been as good if not better this year compared to last, but he’s more a facilitator than scorer. Despite earning the #1 seed and making it to the Eastern Conference Finals, Danny Ainge recognized the deficiencies of last year’s team and focused on retaining size and speed (Al Horford, Jaylen Brown, Marcus Smart) and bringing in multi-tooled free agents and rookies (Kyrie Irving, Gordon Hayward, Jayson Tatum, Marcus Morris, Semi Ojeleye, Guerschon Yabusele).

More examples here and here. However, this season has been very different. Many observant fans have pointed to fewer passes this season, and that’s true: the Celtics aren’t moving the ball as much as before, but the truth is, they really haven’t had to.

Passing Time Frame 2017 2018 Last 6 Games Time Frame 2017 2018 Last 6 Games Passes Made 325.3 292.6 306.2 Assists 25.2 22.8 26.3 Secondary Assists 6.8 3 3.8 Potential Assists 49.5 41.2 43.5 Offensive Rating 108.6 105.9 115.8

After an offensive explosion against the Magic, Stevens said:

“We need to get the ball side to side because that’s usually a good indicator that we’re going to get a good attack … I think that side-to-side movement often precedes paint attacks, and paint attacks often precede good shots.”

“Paint attacks.” Let’s put it in bold for good measure. “Paint attacks.” Attack, attack, attack. Everything runs downhill now so that they can shrink the defense into the key and make it vulnerable.

Yes, moving the ball east to nwest helps, but ultimately, getting paint touches has been the most effective way for Boston to succeed on the offensive end. Whether it’s Aron Baynes or Marcus Morris in the starting lineup, the foursome of Kyrie Irving, Jaylen Brown, Jayson Tatum, and Al Horford put so much pressure on every corner on the court that freeing one of them up off a pick is enough to ignite the offense. When you watch the clips, you’ll notice a stark difference between last year and this year. There were times when the Celtics’ offense looked to run motion just for the sake of running motion and meander through a set. Now, they seemed determined to get a paint touch to kick it out and rotate the ball to find an open shot, and the head of snake has been Kyrie Irving.

Brad Stevens has weaponized Kyrie Irving's one-on-one scoring ability and surrounded him with shooters and teammates that can aggressively attack close outs like Jaylen Brown and Jayson Tatum. Irving is averaging fewer assists as a Celtic than all but one of his six seasons in Cleveland, but that doesn’t mean he’s had less of an impact. Because of his finishing ability in the restricted area, Irving coming off a pick puts the opposing teams’ defense into high alert. It sets off a chain reaction of help defense and switches that Boston has expertly taken advantage of.

Some teams have tried to overplay and crowd Irving, and that’s where Horford has excelled. He’s averaging a career-high 5.4 assists per game, and this is arguably the best he’s ever been. He’s hitting a remarkable 45.6% of his 3s and has had laser focus on getting efficient shots. To date, he’s at a 62.2 eFG%.

Of course, not everything has been generated out of the PnR, but the Celtics have been much more deliberate about setting screens and getting their athletes into space, particularly Brown and Tatum.

These are elements that just didn’t exist last season. Remember all those meandering Jonas Jerebko drives that led to awkward hook shots, or whenever the slightest hesitation by Kelly Olynyk would lead to shot put, flip shots in the paint? Those have all been replaced by hard cuts and rim runs by Daniel Theis and Aron Baynes.

What’s scary for the rest of the league is that Gordon Hayward will eventually be back, adding yet another drive-and-kick threat to Stevens’ arsenal. Tatum and Brown will finish the season at ages 20 and 21, respectively, and are already ahead of schedule in their development. Irving is just entering his prime, and Horford has reinvented his game and doesn’t look to be slowing down.

I’ll be the first to admit that there was a beauty to how the team played before: players danced around the floor in freelance choreography and the ball moved like with purpose and without ego. It was poetry in motion. Now, their pace is slightly down (98.25 vs. 99.32), and they’re not moving the ball as much, but to be clear, this is a team that knows what it wants and now has the personnel to get it.