I am looking at a tennis system using sort of the same principle. Taking the world ranking of a player and then dividing that number by the roung no. they went out in in their most recent tournament + the number of matches won against opponent. e.g Joe has a ranking of 60 went out in round three last tounament and has beaten Jim 3 out of 5 times his rating would be 60/3+3 = 10. Jim has a rating of 50 went out first round last tournament and has won 2/5 against joe his rating would be 50/ 1+2 =16.66 the player with the lowest rating would be the selection. Also room for adding extra points to the division side if one player is suited by the court, one player had a long tough match in the previuos round etc. Haven't bet yet but am starting to investigate previous results with positive signs. Any thoughts.