Green Day's bassist told Rolling Stone about what was going on backstage before the festival gig that lead Billie Joe to rehab. 

"It was very tense back there. They locked us in a room for about six hours. I won't say 'locked'. But I didn't want to hang out in the hallway with everybody's entourage. I felt like a rat in a cage. It was a confined space with a lot of weird people around, people we didn't know wandering in and out.

"When Billie showed up, it was, 'You're not right. What's going on?' I kept an eye on things, and it just went progressively downhill. Me and Billie - we don't play like 12-year-olds anymore. But at one point, I was like, 'Let's goof around. Somehow, we ended up wrestling backstage. I thought, 'If I can just get some of this out of him...' But with the mood depressants and alcohol, it doesn't end up in a jovial party."

MORE