My best guess is that he just isn't being taken seriously by coaches. .
Could be part of it.
There's a lot of politics working against him. He wasn't a high draft pick. He's undersized. He's not a natural PG. He didn't start building a reputation until college.
Memphis is holding one of the top PGs in the NBA - but he does get banged up a lot. The #2 PG is Udrih, a steady guy and unfortunately they just signed him to a contract so he's locked in. The #3 was Calathes out of FLA but good news here, he signed to play overseas. So Russ might stick. Andrew Harrision is also in the mix.
Their roster is littered with good players. Opening night they go with 12.
G/Conley, Udrih, Lee, Carter, Adams
F-C/Gasol, Randolph, Green, Allen, Barnes, Stokes, Wright
That's 12 with rookie Martin/Harrison and Russ Smith in the mix. My guess is this is looking dicey for our guy he'll need an injury in camp to help his cause.