One of the reasons the Celtics were able to defeat the 76ers in the second round of the 2018 NBA Playoffs was because of their defense on Ben Simmons. The favorite to win Rookie of the Year this season, Simmons came into the series playing as well as anyone else in the NBA, only to see his production fall across the board against the Celtics. He still averaged 14.4 points, 8.2 rebounds and 6.4 assists over five games, but Simmons turned the ball over at a high rate and was never able to get into a rhythm.
It contributed to the 76ers scoring a miserable 98.2 points per 100 possessions when Simmons was on the court compared to 117.9 when he was on the bench.
For the Celtics to keep their magical season alive, they'll need to have similar success defending LeBron James in the next round. James is a different player to Simmons, and yet there are similarities in how they approach the game. Not only are they both forwards who function as the primary ball handlers on offense, James and Simmons are at their best when they're creating scoring opportunities for themselves and others out of the paint, which is why the Celtics could use the same defensive scheme against James as they did against Simmons.
If they do, a lot of the responsibility will fall on the shoulders of Al Horford, who defended Simmons more than anyone else on the Celtics. While Horford alternates between playing power forward and center for Boston, he's nimble enough to defend three positions and strong enough to keep more athletic players from bulldozing their way to the basket. Horford didn't prevent Simmons from scoring 28 points on 13-for-26 shooting when they were matched up together, but it wasn't something Simmons or the 76ers could easily exploit.
The same went for Giannis Antetokounmpo in the first round. Even though Antetokounmpo scored 62 points on 24-for-44 shooting when Horford was his primary defender, Horford defended him well enough to avoid needing his teammates' help to slow him down. It's all teams can realistically do against dominant scorers like Antetokounmpo without double-teaming them.
However, Horford and the Celtics won't be able to defend James in the same way they did Simmons and Antetokounmpo. Unlike them, James has developed into a threat from both midrange and the perimeter. According to NBA.com , he made 38.9 percent of his shot attempts from midrange and 36.7 percent of his shot attempts from 3-point range this season. His 3-point shot has slipped in the playoffs, but he's converted 52.1 percent of his midrange attempts thus far.
For that reason, the Celtics might look elsewhere on their roster.
The player who defended Simmons the second most in Boston's series against Philadelphia was Marcus Morris. Morris has more success guarding Simmons than Horford, holding him to a total of seven points on 3-for-13 shooting . He also has a history with James, having developed a reputation of being a "LeBron-stopper" when he was with the Pistons, though he's been less successful in that matchup in recent years.
Then there's Semi Ojeleye, who spent more time on Antetokounmpo in the first round than Simmons in the second round. Defending James is a tall task for any rookie, but Ojeleye has the size to battle with the four-time MVP in the post, where he was unstoppable against the Pacers and Raptors.
The problem for Ojeleye comes on the other side of the floor. Having made only 32.0 percent of his 3-point attempts during the regular season, the Cavaliers will dare him to beat them from the perimeter whenever he's in the lineup.
It's a similar case with Marcus Smart. Despite not being as tall as Ojeleye, Smart is strong enough and scrappy enough to wear James down on switches. If he can make an impact on offense - Smart is one of the least efficient scorers in the league - he could give them the two-way impact they need to get the better of the Cavaliers.
Jaylen Brown and Jayson Tatum are also options for Stevens, but Brown is dealing with a hamstring injury and Tatum's scoring is too valuable for them to have him chase James around on defense. Based on how much the Celtics struggle to score when they are on the bench , they can't afford for Brown or Tatum to get into foul trouble when defending James either.
The combination means the Celtics will defend James by committee. It rarely matters who the primary defender is on him because he's mastered how to create and attack mismatches. It'll be a factor when Terry Rozier, Aron Baynes, Greg Monroe and Shane Larkin on the court, as they each have limitations James will be able to pick on. Whereas Rozier and Larkin don't have the size to keep up with James in the post, Baynes and Monroe don't have the foot speed to keep up with him off the dribble in isolation.
What matters more is the Celtics have five players on the court at all times who are comfortable defending James to prevent him from being able to dictate the matchups. It's something that helped the Celtics contain Simmons in the second round, particularly in Game 2, when he scored one point in his 31 minutes on the floor.
"Al (Horford) starts the game on [Simmons]" Brad Stevens said . "Marcus Morris, Semi (Ojeleye), Marcus Smart will just rotate. And we're just trying to keep them in front; it's hard to do... Trying our best to keep him in front and - he's really hard to guard with a smaller player because he's so big and strong and shifty. So, we just - we're fortunate to have a bunch of bodies to be able to kind of rotate guys."
Simmons and Antetokounmpo prepared them from this moment. Now it's time to see if it helps them do what the Pacers and Raptors couldn't.