To pervert a social practice is to engage in it while subverting a defining end. Sports and other games are social practices one of whose internal ends is score (which generalizes victory). To throw a match is, thus, a form of perversion: it subverts the defining end of score.
Interestingly, cheating is actually a case of throwing a match. To score one must follow the rules. Thus cheaters don't win: they at most appear to. Their cheating subverts score, a defining end of the game. Cheating is, thus, a form of perversion.
The difference between the cheat and the paradigm case of throwing a match is that the cheat seeks to make it look like he did well at the game while the ordinary thrower of a match doesn't.
