Here's what the trade market for Dwight Howard looks like

With the Houston Rockets making calls to gauge interest in former All-Star Dwight Howard, The Vertical takes a look at why it could be hard for them to move the 30-year-old center, some possible trade partners, as well as the specifics of Howard’s current contract.

The contract

Dwight Howard is in the third year of an $87.5 million contract signed in 2013.

The current cap hit for this season is $22.3 million, plus a trade bonus that is currently $600,000. The Rockets would pay this bonus to Howard if he is traded. For trade purposes, $22.9 million should be the number the Rockets and opposing teams will use.

Although Howard is under contract through 2016-17, he can opt out of his contract by June 29, thus making him an unrestricted free agent.

The Rockets' trade rules and hard cap situation
Because Houston is a luxury-tax team, the Rockets can only acquire players who are within 125 percent, plus $100,000 of Howard’s contract.

The Rockets are also hard capped and cannot exceed the $88.74 million threshold the league mandates. Currently the Rockets are $525,000 below the tax apron.

Why it could be hard for Houston to find a partner
Several factors will limit potential trade partners for Howard to a small pool of teams.

Howard has missed over 50 games the past two seasons with a variety of ailments. Although Howard’s minutes have been high over the past few months, one has to wonder how much longer his body can hold up.

A team acquiring Howard has no assurance he will sign come July. Unless Houston gives permission, teams are not allowed to make contact with Howard.

Factor in that the Rockets also have eyes on All-Star Kevin Durant this summer. Adding additional salary could make it difficult for Houston to create cap space to sign Durant.

It will be hard to make a deal with any Western Conference team above Houston in the playoff race.

The top-five West teams – Golden State Warriors, San Antonio Spurs, Oklahoma City Thunder and the Los Angeles Clippers – do not need a center. Although the Grizzlies' Marc Gasol recently broke his foot, Memphis does not have the picks or assets to get a deal done.

Would Houston try and make a deal with the three teams they are chasing for a playoff berth?

In Dallas, the Mavericks' Zaza Pachulia has been one of the most improved players this season. Why trade for a player like Howard when the Mavericks can sign him outright this summer. Utah has Rudy Gobert anchoring down low. Trading for a player like Howard does not fit the rebuild the Jazz have gone through the past few years. The Trail Blazers have been the feel-good story this season with their young core of players. Like the Jazz, adding Howard to the mix goes against how the Trail Blazers have rebuilt their team.

The teams in the lottery either do not have the assets to get a deal done or it would not make sense from a roster standpoint to give away future assets. The Nuggets have the players and draft picks to make a deal, but why do it? Denver is out of the playoffs, has built a nice young core with some veterans and will have ample cap room this summer.

So where does that leave the Rockets?

The team with the players and picks to get a deal done without touching the core would be the Boston Celtics.

The Celtics have a treasure chest of draft picks and expiring contracts, something that would benefit the Rockets in the long run.

Here is a look at a hypothetical trade that could work for both teams:

Houston receives
David Lee
Jonas Jerebko
2016 Boston first-round pick
2016 Dallas first-round pick

Boston receives
Dwight Howard
Montrezl Harrell

Although this trade could knock Houston out of the playoff race, the Rockets would be able to add two first-round picks, as well as their own first if they miss the playoffs. The Rockets currently have the 13th pick in this year's draft and will send it to Denver if they make the playoffs. With Lee’s expiring contract and Jerebko’s non-guaranteed salary for 2016-17, the Rockets could have close to $27 million in cap space. Good enough for a max salary in free agency.

For the Celtics, the addition of Howard could move them closer to the level of Cleveland and Toronto. Acquiring a player like Howard without moving any of their core pieces would make the Celtics a dangerous out come the spring. The Celtics also would not have to move the unprotected 2016 and 2018 Brooklyn Nets first-round picks or Memphis' future first-rounder.

This deal would not hurt the Celtics in the summer if Howard does decide to walk. Boston would have the same cap space if it would have kept Lee and Jerebko, just minus two first-round picks in the mid 20s.

Aside from Boston, there is a limited amount of teams in the Eastern Conference with the potential to do a deal.

The one team that has plenty of assets and players to make a deal is Toronto. However, center is not a position of need for the Raptors.

A team like Philadelphia that has plenty of picks and cap space now could just sign Howard as a free agent in July. There is no need to risk assets to chase him at the trade deadline.

Two teams fighting for their playoff lives and missing their starting centers are the Chicago Bulls and Charlotte Hornets.

The Bulls certainly could offer up a package of Joakim Noah, Taj Gibson and their own first-round pick for Howard. The tough part with this type of trade is that the Bulls are in the luxury tax and would take on additional salary, thus resulting in more luxury taxes. For Houston, the first-round pick could essentially be better than the ones Boston is offering. Although Gibson has been a high-level sixth man for Chicago, the Rockets would have to take on Gibson's contract for next season.

Charlotte has played some of its best basketball of late and is currently holding onto the last playoff spot in the East. The Hornets could put a package together of Al Jefferson, Marvin Williams and a 2016 first-round pick, protected Nos. 1-10 for Howard. Of the trades mentioned above, this deal makes the most sense for both parties. Obtaining a player like Howard in Charlotte would likely see the Hornets in the playoffs come April. For Houston, the Rockets would still have a chance of making the playoffs while also obtaining a valuable first-rounder. Although injured, Jefferson could be back on the court in early March.

With a limited market and plenty of questions to answer in the next week, trading Dwight Howard is not as easy as it sounds.

The Vertical Insider Bobby Marks is a former longtime assistant general manager with the Nets.

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