Actually, i m not too sure to what level of "kelongness" they can achieve nowadays. I suspect very high level now. During Malaysia Cup, they can even control up to the mins of the goals. 2 World Cup ago, Brazil Vs China. Brazil was actually the underdog in that particular match due to Asia Handicap.
All they need to do is to tackle a few of the key players from each team. Not necessary the whole squad.
In the mid-90s in S'pore, number of penalties also can!!!! Ref kelonged.
Tackling a few key players from each team? Yes, you are right. There was one match whereby a fixer thought it was done deal. His players did not sabo him. He never expected another fixer involved. Best of all, each fixer bought a team and both teams were supposed to lose! No one wanted the ball. Not sure how it ended. Story was told to me quite sometime back.