Any sports fan is all too familiar with micro-bets, and the problems they cause. A micro-bet is when bookies offer odds that a particular ball in a cricket match will be a no-ball, for example, or a given serve in tennis will be a fault.

These bets on small events during live play have been linked to sporting corruption - those in the know make hefty profits in betting markets because a player agrees to bowl that no-ball or serve that fault at a pre-determined point in play.

Now, we have found evidence that more than a third of regular Australian sports gamblers are making micro-bets using offshore operators - and worse, this dangerous type of betting is very strongly linked to problem gambling.

Don’t be fooled into thinking micro-betting means small bets. The “micro” refers to a small event within play - but the sum wagered can be huge.

Micro-betting is technically legal for Australian licensed operators. But sporting bodies have not approved it, owing to the difficulty of policing the integrity of their sport given the notorious instances of corruption.

Despite calls for micro-betting to be outlawed completely, we found that Australians are using many offshore operators to engage in micro-betting - operators who are not supposed to offer services to Australian punters but do anyway.

In our most recent paper, in a sample of 1,813 regular sports bettors, we found 667 (36.8%) had bet on micro events in the past 12 months.

Of those, an alarming 78% were classified as problem gamblers.

Only 5% of those making micro-bets were non-problem gamblers, with the rest at some risk of developing gambling-related problems. And when we looked at only those who bet on micro events, those classified as problem gamblers were also likely to place a higher proportion of their bets on micro events. It’s important to note we recruited many regular (rather than occasional) sports bettors, leading to a higher representation of problem gamblers in the sample (46.8%). Nevertheless, the relationship between problem gambling and betting on micro events is striking.

Because micro-betting markets open and close fast, usually over just minutes, this betting needs to be impulsive, and those classified as problem gamblers tend to be impulsive. Also, this is yet another way to bet, and people classified as problem gamblers tend to gamble in many ways - sports, races, pokies - at venues, by telephone, and online.