Boston Celtics need to juice their three-point attack

The Boston Celtics may be pumping the breaks on grand expectations but with the addition of Al Horford, they look like one of the handful of teams that could realistically challenge the Cleveland Cavaliers for control of the Eastern Conference.

The Celtics had a strong season last year and, somewhat quietly, worked their way into at least some aspect of the Golden State Warriors’ magic formula. One of the things that makes the Warriors so good is that they play at a fast pace offensively, getting themselves easy looks before the defense is set, without giving up the same quick offense to their opponents. The “fast-offense, slow-defense” is something of a golden goose that not many teams have been able to capture.

Last season the Warriors and Celtics had the fastest and second-fastest average offensive possessions, according to Inpredictable. They only allowed their opponents the 26th and 24th-fastest possessions. By points allowed per 100 possessions, the two defenses were equally efficient last season but the Celtics were roughly league-average on offense, which is where they’ll need to improve most to really make a run at the Cavs. All their early offensive opportunities buoyed their efficiency but Boston was only 25th in the league in points per possession after a made shot by their opponents.

For the Celtics, reaching their ceiling means keeping all of the benefits of fast-offense, slow-defense in place, while also finding a way to be more efficient in their half-court sets. Their roster excels in an open-court game but, other than Isaiah Thomas, the Celtics didn’t have a clear point of attack in the half-court. They lacked multiple options who could bend the defense and create good open shots for his teammates. The hope is that Al Horford can help in this regard, particularly in creating open three-pointers.

Last season the Boston Celtics finished 11th in three-point attempts game, but a frustrating 28th in three-point percentage. Just four regular rotation players — Kelly Olynyk, Jonas Jerebko, Avery Bradley, and Isaiah Thomas — made better than 35 percent of their three-pointers.

One of the interesting quirks about the Celtics’ three-point shooting last season was the distribution of attempts across the shot clock. Boston attempted 5.3 three-pointers per game during the first six seconds of the shot clock, third-most in the league behind the Houston Rockets and the Golden State Warriors. Threes that early in the shot clock are generally coming in transition, a typically high-value shot against a scattered defense.

If we focus on just the last 18 seconds of the shot clock, the Celtics ranked 15th in three-pointers attempted per game and 25th in three-point percentage. Again, an example of how well their offense played in transition and how much harder they had to work against set defenses.

Horford generated 6.6 assist opportunities per game last season, third among centers. In addition, 102 of his 263 assists on the season (about 39 percent) were on three-pointers. The area outside of the paint but inside of the three-point line is a breeding ground for assists. Horford is a much better passer than any of the bigs Boston had on the roster last season and he’s particularly effective in that area. Either through post-ups, elbow touches, or passes off the catch in the pick-and-roll, the threat of Horford’s scoring and his ability to move the ball should make things a lot easier on Boston’s outside shooters.