Just use something like this:

Two participants. The points gained for victory of that match is calculated based on the difference of points between them.

If there is a 100 point difference between the two and the lower ranked person wins, they get 90% of the point difference between them. If the higher ranked one wins, they get a flat amount, such as 25 points. In the event that 90% of the point difference is less than 25 (in that they are very close in rank to each other), then the winner would get a flat 25 points.

Something like that.