The Cleveland Cavaliers wanted to create cap space to facilitate a max offer for LeBron James and the Brooklyn Nets had been targeting Jarrett Jack for months, creating the framework for a trade that needed a third team.

The Boston Celtics were more than happy to grease the wheels, adding to an abundance of long-term assets in the process.

Cleveland will trade Jarrett Jack and Sergey Karasev to Brooklyn and Tyler Zeller and a protected first-round pick in 2016 to Boston, shedding approximately $9.5 million in salary.  The trade helps give the Cavaliers $21.7 million in cap space, spurring speculation that LeBron could return to his home state and the franchise that made him the first overall pick in 2003.

The Cavaliers will also acquire the draft rights to Edin Bavcic and Ilkan Karaman from the Nets. While the Cavaliers are the principal team in the deal, Boston will also acquire Marcus Thornton from Brooklyn to complete the trade.

The Celtics will reportedly surrender a future second-round selection, but is unlikely to be conveyed since it is top-55 protected.

Brooklyn needed help in the backcourt after Shaun Livingston signed with the Golden State Warriors as a free agent. The Nets and Cavaliers reportedly discussed Jack last February before Brooklyn acquired Thornton from the Sacramento Kings.

Danny Ainge and Mike Zarren are able to add a pair of assets in Zeller and a first-round pick for the cost of Thornton’s expiring $8.5 million contract. Boston has so many future draft picks that parting with a second-rounder was an easy decision.

The Celtics were able to take on the salaries of Zeller and Thornton thanks to the $10.3 million trade exception they acquired from the Nets last offseason in the Paul Pierce-Kevin Garnett deal. It might be a good idea for Mikhail Prokhorov to bar Billy King from negotiating with Ainge in the future.

Zeller gives Brad Stevens a much-needed big body and the 24-year-old could still develop into something more than he was in Cleveland, but he’ll never be the rim protector that Boston is lacking. At his price point and experience, he should be a nice option off the bench.

He averaged just 15 minutes and 4.1 attempts in 2013-14, but Zeller shot 53.8% from the field and his Total Rebound Percentage (15.1%) ranked third among Cleveland’s regulars. His per 36 numbers last season were solid -- 13.7 points, 9.7 rebounds and 1.3 blocks.

Thornton, who will play for his fourth team since he was drafted 43rd overall in 2009, will provide scoring and not much else for the Celtics. He has averaged 13.4 points per game in his career, but never shot better than 45.1% over the course of a full season. His shooting percentages have all trended downward over the last three years, including a career-low 39.4% in 2013-14.

Primarily the top scorer off the bench throughout his career, which had included 126 starts (341 games), Thornton tends to use up several possessions while rarely finding teammates in position to score. He’s a better shooter, but in many ways he will be Jordan Crawford 2.0.

As you might expect, Cleveland’s 2016 first-round pick is the biggest part of this deal from Boston’s perspective. The selection is reportedly top-10 protected for three years until it becomes completely unprotected in 2019. With Kyrie Irving, Andrew Wiggins (or Kevin Love) and possibility LeBron in the fold, the Celtics should except to receive the pick in the first possible draft.

Grade for the Celtics: A-

It’s hard to assume what else the Celtics could have done with the $10.3 million trade exception, but receiving what they did is a very nice haul. Adding a seven-footer to your rotation and a first-round pick is an obvious win, but Thornton’s expiring deal brings other options as well.

A playoff contender might be interested in acquiring Thornton, who would be due just a portion of his $8.5 million salary, at midseason to bolster their bench.

I mentioned Love above in regards to the Cavaliers, but Ainge is still believed to be in the hunt to acquire the All-Star from the Minnesota Timberwolves. An additional pick in the debt column should help Boston’s cause if they do engage in serious talks with Minnesota.

Here is the breakdown of the first-round picks the Celtics have through 2018:

2015: Own, Clippers, 76ers 15-30 (via Heat)

2016: Own, Nets

2017: Own or Nets, whichever is better

2018: Own, Nets

The Celtics have a ton of tools to execute a successful rebuild, but will have to find the perfect combination of using picks and dealing them for established talent over the next four years.