Tony Stewart retired from NASCAR but he's still out there racing dirt tracks. On Friday he was in Jackson to run at Jackson Motor Speedway. 

Stewart's engine blew after one lap leaving some fans understandably frustrated. One fan heckled him while he was signing autographs. In a video posted on Twitter, Stewart eventually loses it and sprints over to the man and throws one punch which sort of connects with his head.

FYI - There's lots of naughty language in the video.

Given that the thing that sent Stewart over the edge was when the heckler replied to Stewart's single middle finger with two middle fingers and yelling "Hey Tony, I’ve got two of them," I'm a little surprised that this was the sort of insult that caused him to go violent. I know that the middle finger is supposed to be an insult, but it doesn't exactly cut to the bone.

Grow up, Tony.