Westerhof, Van Der Duim, and a Strong Whiff of Match Fixing

This afternoon at the ATP Meerbusch Challenger in Germany, all eyes were definitely not on a first-round match between Dutchmen Boy Westerhof and Antal Van Der Duim. Both are ranked outside the top 250, neither has ever cracked the top 200, and both are in their late twenties.

It appears that the two players assumed no one would be watching. Before the match, the markets on Betfair were very suspicious:

For those of you not accustomed to parsing betting markets, here’s a summary of what the market thought was going to happen:

  • Van Der Duim’s chances of winning the match were between 75% and 80%.
  • Van Der Duim’s odds of winning the first set were roughly 35%.
  • There was a better than 50/50 chance that Van Der Duim would win the match in three sets. The odds of any other specific outcome (e.g. Westerhof wins in three) were minuscule in comparison.

The match odds in themselves might have raised a few eyebrows, but could be written off as owing to Westerhof’s recent run of poor play, or perhaps some information gathered on site about a nagging injury. When combined with the other markets, however, it’s clear that something very fishy was going on.

The match went precisely according to script. After Westerhof took the first set, 6-4, the market got more and more confident about Van Der Duim winning the second set:

Van Der Duim remained the favorite even after going down an early break in the second set. Shortly thereafter, with no cameras watching, Westerhof seems to have decided not to waste any more time:


In the end, Van Der Duim beat Westerhof, 4-6 6-3 6-3. No one following the betting markets was at all surprised.

Nor should we be shocked that this sort of thing happens. With the middling prize money on offer at Challenger events–Westerhof will get about $500, and if Van Der Duim loses in the next round, he’ll be awarded about $800–there’s more money to be made by losing matches than winning them.

While we don’t know how often matches are fixed, something was very wrong about this one. Because the markets so blatantly telegraphed the fix, it poses an important question to the sport’s governing bodies. If they don’t take this opportunity to act, it will send a very clear message to Challenger-level players that match-fixing is acceptable practice.

(Thanks to the three Twitter users quoted above, who brought this match to my attention.)

5 thoughts on “Westerhof, Van Der Duim, and a Strong Whiff of Match Fixing”

  1. There are almost no situations where a best of 3 match is a favorite to go to three sets. If the market priced a player as greater than 50% to win in exactly 3 sets, that alone is compelling evidence of match fixing.

  2. Strongest whiff of a fix I’ve ever smelled. Never, and I mean never, will a bookie (yes, Betfair isn’t a bookie, and that’s half the issue) start Player A as a favourite over Player B, and make Player B the favourite to win the first set. And absolutely, after winning the first set, let alone going up a break in the second, will the player leading not see his odds shorten significantly.

    What’s curious to me is what the person(s) posting these odds on Betfair was trying to achieve. By pricing the markets as they did, the betting pros were going to smell this out very quickly (and really only the pros would be scanning Challengers for betting opportunities). You’d see this – and I did – and you would spot the longer odds as pure sucker bait. It’s quite possible in my opinion that the Betfair prices could have been picked off by an opportunistic pro who spotted exactly what the fixers were signalling. I’d be quite surprised in fact if they managed to make any money on this gig.

    My best guess though is that these were rank amateurs – if they have one degree of connection to the two players, that would confirm it – who looked at the famous Davydenko-Vassallo Arguello match (which imo was not fixed, but was profited on by people who had an inside track on a Davydenko injury) and figured they’d give it a try.

    But both the players and the Betfair punters ignored the cardinal rule of fixing – you’ve got to make it look good. This didn’t even come close.

  3. I might have given Team Fix too much credit in my comment yesterday.

    Still reckon they are amateurs, they left a clear trail by hiking into four separate markets with foreknowledge of what was going to happen.

    I gather the TIU will be investigating, and if I were them, here’s what I would be looking for. For a normal bookie, who would price a tennis match through a predictive model, they would have picked up the ruse immediately. A flood of money onto all of: BW winning Set 1, AVDD winning Set 2, AVDD winning the match, and the winning margin being AVDD by 2 sets to 1 would have resulted in the model being switched off. These separate markets are all too correlated to sustain basically completely irrational swings of the magnitude seen before the match started. The bookie would have shut down the market.

    BetFair is not a bookie though, it doesn’t run a pricing model for matches, so correlated markets moving in opposite directions is not going to cause a break in a model.

    So one of two things happened. Either Team Fix piled into four separate BetFair markets; if this happened, they should be rumbled before the end of this week. BetFair will already know who they are. The alternative scenario is bit more complicated. Team Fix could have piled into these four separate markets at four separate bookies. These bookies each in turn could have moved to BetFair to lay off their risk, and that’s what caused those markets to go crazy. Under this scenario, it will take longer to piece together the story. There’s more disparate information to gather, more work to tie it all together.

    But basically someone threw a bunch of money on four tightly inter-related markets. In the betting world, there are only three types of people who do that – (1) people who have no idea what they are doing; (2) dead-enders desparately hoping for a change of luck; or (3) people who know the outcome in advance. No-one playing the markets on the square with a clear head would do this.

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