Don’t try this at home.
Pro Wrestling World shared a clip on Facebook in which a wrestler knocked himself out during a match. In the video, the wrestler goes for a 450 splash, but his opponent moves, so he lands head-first on the mat. The individual is clearly knocked out upon impact. His oppponent then drags him into position so he can hit a move from the top rope. However, a medical official enters the ring and checks on him as the referee seemingly stops the match. The identities of the wrestlers involved are unclear.
The video can be seen here.