A day after acknowledging in a podcast interview that he has tried marijuana for back-pain relief, Warriors head coach Steve Kerr said he hopes the NBA’s upcoming collective bargaining agreement allows players to use cannabis for medicinal purposes. “The league should look into the use of medicinal marijuana for pain relief,” Kerr said during his pregame news conference Saturday night. Kerr, who missed the first 43 games of last season with complications stemming from back surgery, has tried marijuana twice within the past 18 months. “Having gone through a tough spell over the last year with my own recovery from back surgery, and a lot of pain, I had to do a lot of research,” Kerr said. The stuff is dangerous — the addiction possibility, what it can lead to, the long-term health risks. [...] in the NFL, NBA, it’s a business, so you don’t want your customers thinking, ‘These guys are a bunch of potheads.’ In a 2014 interview with GQ, NBA Commissioner Adam Silver said, It’s our strong preference that our players do not consume marijuana.