I believe it was the Bills vs. Raiders game and the Raiders receiver started casually jogging towards the end zone well before he got there and the Bills defender chasing him tackled him in the end zone and got a penalty for that. I don't think defenders should be penalized for that. If someone starts celebrating before they get into the end zone, the defender should be able to take a shot at him without getting penalized. I can't stand it when they start celebrating before they get into the end zone. After they score, I don't really care, although I'm glad they have put restrictions on excessive end zone celebrations. But if I was a coach, I would tell my players I would never be angry at a penalty for hitting someone in the end zone who starts celebrating before they get there. I would tell them to do it like Adam Sandler did in the waterboy, a jumpkick with both feet to the person's chest. So what, it's a 15-yard penalty on the kickoff. The kicker kicks it out of the end zone and you get it on the 20. But please, act somewhat like a professional and score the touchdown first and then do your celebration.