Open Day, or open season?

Seeing that Tony McCoy scored an in-running win for punters at 999-1 yesterday (when he came from 10 lengths back aboard the 9-2 shot Open Day in the racingUK.com Juvenile Novices' Hurdle at Market Rasen) brought back memories of the first such bet of its kind on Betfair - when McCoy re-mounted Family Business at Southwell in 2002.

You'd think that 1000-shots winning was a very rare occurence; so, too, 1.01 shots being turned over. But how rare? I asked the clever people who can dig into Betfair's audit trail to find out how often either has happened.

The answer is that there have been 537 bets landed at 1000 on Betfair to date, ranging in size from £2 (which accounts for 178 of them) to an astonishing £277 on Optimus Prime at Thurles on 8th November 2007, after the leader fell three out.

Meanwhile, 57,392 bets (on roughly 17,000 events) have been unsuccessfully backed at the minimum odds of 1.01, of which 3,167 were people putting £2 on what they felt to be a certainty to win just 2p! At the other end of the spectrum, last-gasp upsets have on occasions cost a backer more than £100,000.

Tottenham's late, late show, when they came back from 4-2 down on 89 minutes to clinch an equaliser three minutes into added time in the London derby on 29th October 2008 was the second-biggest ever: one backer had put almost £160,000 on an Arsenal win at the minimum odds with only minutes left.

But the biggest example of a 'sure thing' not coming off cost a punter an astonishing £200,000 when he backed Australia to win the fifth one-day international against South Africa in 2006, after they had scored a world record 434 for 4 in their 50 overs. South Africa got to 438 for 9, and won by a wicket with one ball to spare.