They don't, but the second-rounder is only a min deal, so it can't go away. If anything, it would go up if the Spurs signed a vet with the money. It would actually cost money to replace that with a vet. Speaking of that, I was actually off on my numbers for the second rounder and rookie slots. The hold is $815,615, not $1,471,382, also Forbes and Bertans should count as $1,312,611 each. All that gives the team like $1.5 Million in extra space. Not nothing, considering how tight they are. Between that and keeping the split guys in Austin most of the year, they probably have enough to give Simmons and Patty pretty decent contracts.
I would agree normally. But him and Manu walking with no one Murray, picks and min contracts to replace them would be hard to imagine. Moving on from Simmons would give the Spurs another $800k or so, which makes it completely possible to keep Mills.