Only a few days from the start of Nuggets training camp, Michael Porter Jr. isn’t thinking about anything but basketball. At least that’s what the Nuggets star forward claimed Thursday, as the deadline for an early contract extension inched closer. The Nuggets have until the start of the season to reach a deal with the 23-year-old or he’ll enter next summer as a restricted free agent. Porter, fresh off a healthy offseason that featured a week-long workout with Warriors sniper Steph Curry, said he’s leaving negotiations up to his agent, Mark Bartelstein. “It’s a thing that’s on the radar, but, you know, I try to let my agent do his job,” Porter said.