In this market SportingIndex simply pick two golfers and predict who will finish higher at the end of the tournament.
The result is the number of shots that one beats the other by. If either player misses the cut, both players' halfway scores will be doubled. For this bet it does not matter where the two golfers finish in the tournament, or how any other competitors perform, just the two players on which you have placed your bet.
For example, in a 72 Hole Match Bet between Colin Montgomerie and Lee Westwood SportingIndex might predict that Westwood would beat Montgomerie by around one shot. As a result their quote would be 0.5-2.0. If you believed that Westwood would continue his good run and that Montgomerie would struggle, you would bet high at 2.0 for the stake of your choice, in this case say £10 per shot.
Had your view been confirmed with Westwood beating Montgomerie by 10 shots (for example Westwood finishing 8 under par while Montgomerie ended 2 over), your online spread bet would have returned 8 times your stake: (10 - 2.0) x your stake = 8 x £10 = £80.
However, had Montgomerie returned to his imperious best and finished on 16 under par and Westwood 10 under par, Montgomerie wins by 6 shots. As a result you would have lost 8 times your stake. As you bought Westwood at 2, you lose two points plus what Monty won by. Here's the calculation: (-2.0 - 6) x your stake = 8 x £10 = -£80.