The chemicals that make up the match head have a relatively low ignition temperature—roughly 360 degrees F. Sliding the head across the rough surface produced a temperature at least this high.

WWE star JD McDonagh smacked his head on "Raw" Monday night after a high-risk move during a tag-team championship match. He ...

A lopsided head to head can scramble players' brains and create strange dynamics. Here is how tennis pigeons cope.