Well this is one way to use your head. Unfortunately.
Goalkeeper Joao Carlos of Brazil's second-tier Boa Esporte experienced a fluky case of Murphy's Law in a recent match. Carlos failed to clear a crossed ball and was out of position. After an opposing player took a shot on goal, one of Carlos' teammates was there to clear it. But the ball ended up hitting Carlos' noggin and flew right back into the net for an own goal.
H/T Dirty Tackle