The SAFA chief attended a joint workshop on match fixing and sports betting in football in Johannesburg on Saturday, with members from Interpol, FIFA and COSAFA also in attendance.
Nematandani blamed a lack of ethical standards for the continued cheating in the sport, saying: "Referees are being bribed and officials are making decisions to benefit themselves and their friends rather than the good of the game.
"And how many times do we still hear about age cheating in junior competitions. It has been going on for a long time now."
He added: "The problem is getting bigger. We need to put in place effective measures to counter this.
"We have to invest more in governance."
This weekend's work shop followed on from the stunning revelations last week which saw Kaizer Chiefs team manager Bobby Motaung arrested in connection with fraud charges relating to the building of the Mbombela Stadium, a 2010 World Cup venue which cost around R1.2billion to complete.
"It is now a matter of public record that we were targeted by a match fixing syndicate before the 2010 World Cup. In March this year FIFA came to investigate and we gave them our full co-operation.
"We hope to have the conclusion of their investigations soon," he added.