As the salary cap contortionists of the NBA, the Boston Celtics have the flexibility to execute their transactions in various ways this summer. In all likelihood they'll waive their cap holds and trade exceptions to sign Amir Johnson using cap space, but the Gerald Wallace for David Lee trade opens up the possibility of them retaining their exceptions to give them more trading versatility going forward this summer.

The Lee trade isn't even done yet, according to Steve Bulpett of the Boston Herald, who adds that the Celtics are "hard at work on potential corollary moves that will give more sense to all of this." In other words, as Danny Ainge reviews the roster as it presently stands, one thing becomes clear: it's too unbalanced.

Contortionists are able to pretzel into unorthodox positions, but balance is the secret to maintaining those funky poses. In order to maximize their potential, the Celtics must find balance, or they'll be at risk of toppling over due to their lack of depth at wing and forward.

Brad Stevens has said multiple times that he prefers a rotation with four big men. But he was put into a bind last season with the amount of depth, and after the acquisition of David Lee, Stevens is in the same spot. The Celtics could also be unable to frequently play small ball if Stevens is forced to use the five serviceable bigs all deserving of the 96 allocable minutes.

With that in mind, it's plausible that the Celtics are planning for their "corollary move" before the Lee-Wallace swap is finalized. Considering the surplus of bigs and guards on the roster, one could potentially be shipped out of Boston, along with a guard, for a position of need at wing or forward.

The Celtics have bolstered their team with their low-risk acquisitions, but they still lack a go-to scorer. Remember, Ainge said at the end of the season that he'd like to add a player with a knack for scoring in the fourth quarter, and they have yet to acquire one this summer.

Here are some players who fit that profile and could be available:

DeMar DeRozan, Wing, Toronto Raptors

2015 Salary: $10,050,000

DeRozan would give the Celtics an All-Star talent who can score outside of traditional sets in the fourth quarter. But, despite scoring over 20 points per game the past two seasons, DeRozan is inefficient, with a career 45.4 eFG%. He accumulates his numbers because of volume, not efficiency, which may work against what the Celtics are trying to build.

But there's no denying he has talent, and the Celtics may believe they can shape him into a better player in Stevens' system. He draws fouls at a high rate, excels in isolation, and could develop into a more productive outside shooter with some alterations to his mechanics. Plus, he has absolutely demolished the Celtics in their recent match-ups.

After signing DeMarre Carroll and Cory Joseph, the Raptors could be looking to move on. They were reportedly shopping DeRozan weeks ago, according to Ryan Wolstat of the Toronto Sun, since they don't want to sign him to a max contract next summer. The Raptors are in need of a power forward, which makes both Sullinger and Olynyk appealing, if paired with Avery Bradley, Evan Turner, or another piece.

Danilo Gallinari, Forward, Denver Nuggets

2015 Salary: $11,559,225

The popular trade target tossed around is Gallinari, as he should be. The Nuggets were shopping him and probably still are today. They are rebuilding and the injury prone Gallinari doesn't factor into their future, as he'll hit the free agent market next summer.

But the Celtics could view Gallinari as a low-risk/high-reward player because of his scoring ability. He's a solid three-point shooter, adding a much-needed stroke to a team starving for perimeter scoring. And he's capable of creating off the bounce, giving them a potential go-to threat other than Isaiah Thomas. At just 27-years-old next season, he could just be hitting his prime.

The Nuggets have plenty of talented bigs on their roster, but need to add all the talent they can get. Adding a big that can stretch the floor like Sullinger or Olynyk would benefit them. Depending on how the Celtics maneuver around the cap could force them to include different players to make the salaries work.

Secondary Targets

These players haven't been involved in rumors, but they make sense, on paper, as targets for the Celtics.

Kevin Martin, Wing, Minnesota Timberwolves

The Celtics were rumored to be talking trade for Anthony Bennett before the draft. The Wolves probably don't view either Bennett or Martin as part of the future, so the Celtics could send assets back their way in return for a package of Martin and Bennett. Martin is one of the premier three-point shooters in the league and Bennett presents upside as the top pick in 2013.

Tyreke Evans, Wing, New Orleans Pelicans

Ainge has long coveted Evans for his tenacious scoring and his versatility. It's unlikely that he'd be available, since Pelicans head coach hinted that he has big plans for Evans this coming season, but talk is cheap.

Kentavious Caldwell-Pope, Wing, Detroit Pistons

Early impressions of Stanley Johnson are strong in Detroit, so they have a fair amount of depth at wing. Maybe Caldwell-Pope could be acquired if a stretch shooting big is sent in return. However, this move wouldn't be very impactful for the Celtics this season, since KCP hasn't proven he can produce consistently.

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