Tactical Issues: Just who are these Bubble Boston Celtics?

The Toronto Raptors and the Boston Celtics finally meet in the playoffs today, after years of their respective fanbases side-eyeing each other. Both teams appear to be a problem for each other, so it won’t surprise to learn that both fanbases will be there to worry and over-analyze every moment of the series.

The Celtics have three of the top five scorers on either team, with their three-headed monster of Kemba Walker, Jayson Tatum, and Jaylen Brown putting up points. The Raptors have at least three (if not four or five) of the top defenders on either team, when considering Marc Gasol, OG Anunoby, Pascal Siakam, Kyle Lowry, and Fred VanVleet.

As for absences, it seems likely Gordon Hayward will miss an extended period of time (e.g. the whole series) due to an ankle injury. Meanwhile, Lowry got through a full practice with the Raptors and seems likely to play (even if not at 100 percent). Nevertheless, this series is shaping up to be a battle of attrition.

Let’s look at what the Celtics have been up to since entering the Bubble.

Lineup and Rotation

As the season has gone along for Boston, Hayward has taken a backseat to Tatum, Brown, and Walker, becoming a versatile complementary player in the starting lineup. In the past, coach Brad Stevens would almost always have at least two of Hayward, Tatum, Brown, and Walker on the floor against an opposing teams’ bench. In the first round against the Sixers, the Celtics were OK going nine or ten deep in their rotation — even without Hayward — often using bench players for a few minutes to buy some time.

As mentioned, Hayward injured his ankle in Game 1 against the Philadelphia 76ers and will likely miss this series against Toronto. As a result, Marcus Smart has taken over Hayward’s minutes, and played as the team’s point guard at times, allowing Kemba to play off-the-ball. Obviously, losing Hayward is a blow to Boston’s rotation, as they’ve got to go a little deeper into an already shallow bench. Still, with Smart playing more, the Celtics’ defensive rating has jumped from 111.0 to 104.5 points per 100 possessions. They’re not a better team without Hayward, but that doesn’t mean the Raptors should take them any lighter.

Defensive Scheme

The Celtics primarily use man-to-man defense and switches for the most part, except when keeping Walker out of a mismatch. They have long, quick, and switchable wing defenders. They can force a lot of turnovers, resulting in transition opportunities. Boston’s starting centre, Daniel Theis gives the Celtics a decent anchor in the middle. While he’s not a big-time rim protector, Theis makes sound decisions defensively when it comes to rotations, help defense, and verticality around the rim.

The Celtics have also shown some strong team cohesion with their zone defense. As with the Raptors, they like to sprinkle in zone defenses now and then throughout a game. We saw it in the first round, as the Celtics would sometimes employ a zone to slow Joel Embiid and the Sixers.

To crack Boston’s defense, opposing teams have tried to target Walker, especially in the post. Considering the size and mobility of the rest of their starting lineup, attacking Kemba makes some sense. However, the Celtics are good about sending double teams or sagging into a zone to clog the paint.

Offensive Scheme

The Celtics run a lot of motion offense, which puts stress on any defense, especially given the scoring punch of their starting lineup. They have several variations/counters for their standard sets, so defenders can’t be caught ball watching. The Celtics also use some variations of Horns sets to get their players in position to create shots inside the arc or to operate out of a post-up for Tatum or Brown. Meanwhile, Walker is dangerous around the perimeter as a player who can create his own shot via simple screen action or through set plays like a double drag. Off the ball, expect Stevens to run some misdirection plays with Kemba slipping/hiding behind an off-ball screen.

Daniel Theis is arguably the most underrated player on Boston, as he’s proven vital to their success. He’s always on-point while running their set plays, ready with the solid screen, and knowing when to pop or roll. What’s more, Stevens trusts him to make a play once he gets the ball up top in their motion offense.

When the Celtics’ offense bogs down, they have various options, but they’ll most likely get to an isolation play from Tatum or Walker, or a pick-and-roll initiated by Walker, Tatum, or Smart. It’s worth noting that the Celtics don’t actually rely that much on isolation plays, but that doesn’t mean their key players aren’t good at scoring that way.

One of the reasons why the Celtics might opt for single coverage while defending the Raptors is that they have successfully put taller, longer, and quicker wings on Fred VanVleet to slow him down. Not to sound to concerned about this, but VanVleet shot 33.8 percent overall against the Celtics in this past regular season.

Coaching

I hate to admit it, but Brad Stevens is one of the best coaches in the NBA today. People talk about Stevens’ after time out (ATO) plays, but he’s an underrated and ruthless coach when he sees an opponent’s weakness.

In the Sixers-Celtics series, for example, Stevens repeatedly torched Embiid’s extreme drop coverage, using it to his advantage to open wide-open pull-up jumpers for Boston. He also knew that Embiid’s gas tank usually hovers near “E” so Stevens kept rotating in new players to bang with the Philly All-Star, while using a zone defense to collapse on any post-ups. After that, Stevens had the Celtics push the pace. No wonder Embiid looked so unhappy.

But hey, at least now we know the Stevens voted for Nick Nurse for the NBA Coaches Association’s award.

Tactical Issues

The Celtics loss of Gordon Hayward means their floor spacing now depends on Marcus Smart shooting well from the perimeter. Smart is a streaky shooter, and he won’t be shy about hoisting them up — sometimes to a fault. This will most definitely be something to watch in the series.

To respond, the Raptors will throw zone defenses at the Celtics, daring them to shoot semi-contested perimeter shots. With Smart moving into the starting lineup, the Celtics don’t have much scoring options off their bench, especially if they think that Enes Kanter is unplayable in this series. In the playoffs so far, foul trouble has also exposed the Celtics’ lack of depth. The core of the team is as solid as anything, but it remains to be seen what can be expected down the lineup.

For the Raptors, the Celtics’ offense presents a different challenge than their previous matchup with the Nets. In that series, Caris LeVert was a one-man show, working to manipulate Toronto’s defense to create opportunities for everyone. Boston is obviously different. They’ve got well-polished offensive sets, and can run them all with three skilled and athletic players — Tatum, Brown, and Walker — who can go ISO if necessary.

While it looks like Lowry will be ready for Game 1, we’ll have to see if he’s fully healthy — especially since he’ll be tasked with guarding one of those aforementioned skilled offensive players. Lowry playing a step slow for Toronto could create a domino effect on the Raptors’ offensive and defensive schemes.

Game 1 Expectations

For the Celtics:

Finding the Right Bench Players

Ever since Marcus Smart moved to the Celtics’ starting lineup, they have struggled to get extra scoring help from their bench. Boston will need someone to step up, as the Raptors will game plan to stop their key players. Staggering their three scorers will make it easier for the Raptors’ defense to slow them down if they don’t get any help from their bench.

Brad Wanamaker and Enes Kanter may be the only steady options Boston has off the bench. There’s also the two Williamses — Grant and Robert — but their playing time was all over the place against Philly. What’s more, Kanter is perhaps the only reserve Celtic who can consistently score. The problem: he’s a complete liability on the defensive end. For his part, Wanamaker only scored 18 points in four games vs. the Sixers. Grant Williams went for 19, but that rookie forward is likely not the answer. It’s a tough equation for Boston to sort out.

Keep Bubble Tatum Going

Tatum has struggled against the Raptors, with his scoring and shooting percentage coming out lower than his season average. Tatum admitted to Jackie MacMullan that he’s had it tough against the Raptors’ defense, which checks out given how good they are at executing their game plan on that end.

Tatum shot almost 45 percent on seven attempts per game from three during the seeding games. And that’s not even the scary part — he’s doing it off the bounce or with a defender in his face. Against the Sixers in the playoffs, Tatum continued his shooting streak, sometimes even pulling up from a few feet behind the three-point line.

However, Tatum’s bottom-two worst perimeter shooting performances in the seeding games came at the hands of the Milwaukee Bucks and the Raptors. It’s also worth noting that while Tatum looked awesome for the most part against the Sixers, he still had a performance (Game 3) where the Sixers were able to effectively slow him down. It will be interesting which of these two trends continues in this playoff matchup.

For the Raptors:

Keep the Three-Headed Monster in Check

We know Stevens will try his best to plan for scoring opportunities for Walker, Brown, and Tatum — and rely on them heavily. Nick Nurse know this too, and as always will tailor the Raptors’ defensive schemes as necessary.

In the past, Nurse has concentrated on making life difficult for Tatum, but that plan has come at a cost. In those games, the Raptors were unable to stop Brown, who has averaged 23 points per game against Toronto this season. It’s quite a jump, especially when you consider he put up just 9.3 points per game against the Raptors last season. Meanwhile, Walker has been humming along against Toronto, averaging 22.8 points per game against the Raptors this season.

Expect the Zone Defense

The Celtics have been successful in playing the Raptors with straight-up man-to-man defense in the past. Knowing Stevens, however, he won’t hesitate to throw some zone in now and then to keep Toronto off balance. Nurse should expect this, and he should expect the zone to stick around longer if the Raptors struggle to hit shots.

We saw this in Game 2 of the Nets series, when Toronto couldn’t buy a bucket from deep; and we saw what it looks like when they’re able to generate — and hit — open 3s. Their offense flowed quite effortlessly and led to easy wins. This is where it will be important for Gasol to step up. Against tough teams, he’s the natural zone-breaker, through both his long-range shooting and play-making and the fact that Boston will likely dare him to let fly from deep. If Gasol can keep the Celtics’ defense — whether in man-to-man or zone — honest, it’ll open up a lot for Toronto.