Despite poor attendances, the atmosphere has been electric at almost every one of the eight matches in the opening phase of soccer's African Nations Cup.

Low crowds are not unusual in opening-round games in Africa's elite competition, but gauging how many fans attend games is difficult as the Confederation of African Football (CAF) and the local organising committee rarely issue exact official attendance figures.

Rows of empty seats in stadiums do not reflect well on the tournament's image in television pictures flashed around the world, even though the fans who have attended have created vibrant, dynamic atmospheres, despite reacquainting the world with the drone of the vuvuzela.

Hicham El Amrani, CAF's general secretary, said that while the tournament was growing in terms of corporate interest and global television audience awareness and was benefiting here because of the improved infrastructure following South Africa's hosting of the World Cup finals in 2010, other problems remained.

Accepting, on the eve of the tournament that tickets were still unsold, including some for the final, he said: "Not many African fans have the budgets or spending power to fly here and it is not always easy to get the right connections in Africa.

"Despite that we are still very optimistic about the future of this tournament and that it will continue to flourish.

"Our viewing figures around the world have improved in recent years by around 225 percent and we hope to keep the momentum going."

Ticket sales are vital to producing a profit at the end of the tournament, with the proceeds handed back by CAF to the national associations and the local organising committee.

El Amrani said that the CAF and the local organisers wanted to see as many fans as possible in the stadiums but so far only the opening game between South Africa and Cape Verde Islands at Soccer City on Saturday had been a sell-out.