The Phoenix Suns have 13 players under contract with full salary protection for 2015-16 and all of them are expected to make the roster when it's set on October 26. Forward Cory Jefferson is not on that list and he is working hard in the preseason to make sure he lands one of the last two spots on the roster. From Zach Buchanan of The Arizona Republic:

"There is a long line of power forwards ahead of Jefferson on the depth chart, including Markieff Morris, Jon Leuer and Mirza Teletovic. ... Jefferson and fellow forward Henry Sims may have the best shot (at making the team from the training camp invitees). But other players who could be released by other teams may skip ahead in line. ... Whatever happens, Jefferson has already beaten the odds in one sense. Since 2005, when the draft culminated with the 60th pick, only five of the nine players who preceded Jefferson as Mr. Irrelevant ever played a second of NBA basketball. Only two of those – Isaiah Thomas and Robert Sacre – are still in the league. Jefferson hopes to join those two as the exception to the rule that the last pick never makes it."

At this point it does appear that Jefferson and Sims will likely get the last two spots, however they could be cut at any time, as Coro wrote.