"I think with Jared and I, we knew right away it wasn’t going to work if we didn’t get along. The first season, I forget what episode it was, but we got heated on set and got in each other’s face and I mean, we went toe to toe. There were no fists thrown or anything like that, and he ended up taking a walk down the street and cooler heads prevailed, and when we got back to our trailers, I knocked on his door and sat down and I was like listen man, that can never happen again because if that’s the road we choose to go down, we are going to be living a different life. And it wasn’t just me, he was like actually on the same wavelength, like I’m glad you came by, I need to get this off my chest, we need to come together if we are going to make this show work, because we’re gonna be spending way too much time together to not have a friendship. And that’s the last fight we’ve ever had."
Jensen Ackles in an interview for Fandom At The Crossroads: Celebration, Shame and Fan/Producer Relationships (p.220)