The Grizzlies, who seem to be hoarding TPEs like no other franchise, could have traded Greene directly for Melo.
Instead, they used up the remainder of their Marreese Speights TPE, which was set to expire on January 22, 2014, to acquire Melo and his $1.3 million salary this coming season. The Grizzlies also received a new TPE, created for Greene's $1.0 million salary (which won't expire until August 15, 2014).
Boston's primary goal in the trade was to get under the luxury tax threshold, which likely means Greene is waived by the team before the season begins.
Boston drafted Melo in 2012 with the 22nd overall pick but they dumped him to get out of the tax.
The Celtics also sent $1.66 million in cash to the Grizzlies to make the deal, about $349k more than Melo will make next season.
So there you have it. Memphis generated another TPE and made a little cash on the deal and the Celtics were able to cut a player that didn't have a guaranteed contract in order to get under the luxury tax. Boston now has 14 guaranteed contracts and are roughly half a million dollars under the tax threshold.
Source: Barring any late changes, Celtics training camp roster is set. Invites: Chris Babb, Damen Bell-Holter, DeShawn Sims, Kammron Taylor.— Baxter Holmes (@BaxterHolmes) September 17, 2013
That opens the door for one of the four non-guaranteed training camp invites--DeShawn Sims, Damen Bell-Holter, Kammron Taylor, and Chris Babb--to make the team on a rookie contract. For those hoping that getting under the tax would free up Ainge to bring in fan favorite veterans like Leandro Barbosa or Chris Wilcox, remember that per the salary cap, only a rookie minimum would fit under the threshold; the minimum for a rookie is ~$490,000 where as a player who has already played in the league for one season is owed at least ~$788,000.