In horse racing, a non-runner refers to a horse that was entered into a race but has been withdrawn before the race takes place.
There are various reasons why a horse may become a non-runner, such as illness, injury, or a change in plans by the trainer or owner.
When a horse becomes a non-runner, it can affect the betting market and the odds offered on the remaining horses in the race.
Bookmakers typically offer a “rule 4” deduction, which is a reduction in the odds for the remaining horses in the race to reflect the fact that there are fewer runners.
The size of the rule 4 deduction depends on the odds of the withdrawn horse at the time it was declared a non-runner.
If the non-runner was a strong favorite, the deduction will be greater than if it was a long-shot outsider.
The rule 4 deduction is typically calculated as a percentage of the potential payout on the remaining horses, and the percentage varies depending on the odds of the non-runner.
It’s worth noting that not all bets are affected by non-runners.
Some types of bets, such as forecast and tricast bets, are voided if one of the horses does not run.
It’s always a good idea to check the latest news and updates before placing a bet on horse racing to ensure that you are aware of any non-runners or other changes that may affect the race.