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What have your experiences about this been? Is match fixing considered a common occurrence in leagues you place bets at?
No experience so far or at least not to my knowledge. I also prefer betting on top leagues like most members. I have heard of match fixing accusations from local sport leagues but it's usually the accuser's words against the accused. No real evidence to support it so I cannot really call the game as rigged. There are bettors that are just sore losers so can't take them seriously.
If you watch the news, maybe you have heard that there are several matches where match fixing is suspected, this also happens in several other European small leagues or even in Asia, there are several former football players in my country and he is telling the truth about match fixing and he one of the players who was bribed with money by football officials at that time to play badly and lose in a final match.
I used to think like you that it couldn't possibly happen and thought people were accusing of match fixing but after seeing statements from former football players who had been involved I thought that it seemed like not only in my country but the football mafia would always be out there playing. in minor league leagues to manipulate bets also in gambling and more.