What does SP mean?
SP refers to the starting price of a horse. For example, a horse may be priced at 4-1 in the morning, but by the time the race starts it's drifted to 6-1. If you backed a horse that drifted in the market with a bookmaker that offers best odds guaranteed, you will be paid out at the bigger price if the horse wins. when looking to get a refund on a 2nd to SP fav offer, your horse must come 2nd to the favourite in the race. In other words, it must come 2nd to the the horse with the lowest odds in the race.