Dumitru is regarded as the most successful coach in the South African domestic competition, and guided the national team as an interim coach for four months until February 2006.
Bafana Bafana bowed out of the World Cup on Tuesday despite beating a crisis-hit France 2-1 in Bloemfontein.
“What I observed with the World Cup is that there has been a lot of excitement across the nation — people who were previously not involved or interested in football came along, sponsors, fans, and others,” Dumitru said. “Now, I’m worried that if they see Bafana not doing well they might say ‘there is nothing in this sport, let’s go back to rugby and cricket’.
“That will be a serious blow to football in this country.”
Dumitru said people wanted to be associated with success.
South Africa is a two-time World Cup champion in rugby, the Springboks having won in 1995 when it hosted the tournament for the first time in the post-apartheid era and in France in 2007. The national cricket team is consistently among the best in the world.
Rugby and cricket have high profiles in South Africa because of that success, but football is the most popular sport in the country in terms of participants.
“We need to convince people to stay in football. It has a massive following in the country,” Dumitru said. “We must not lose hope. We must not lose interest.”
Dumitru said despite the financial success of the South African domestic football competition, it is lagging behind bigger leagues in terms of its playing standard.
“The style of play in the PSL is still kicking and running … There is no creativity,” he said. “That is in big contrast to the leading nations.”
Brazilian coach Carlos Alberto Parreira had worked on improving cohesion and teamwork at the national level, Dumitru said, but South Africa really needed a broader player development programme.
South Africa opened the tournament with a 1-1 draw against Mexico, but a 3-0 loss to Uruguay put them on the path to elimination.
Enock Muchinjo in Pretoria