Tunisia's Ouissen Ben Yahia skips past an Australian challenge

Tunisia and Mali both drew their opening group matches as the Olympic Games football tournament started on Wednesday.

Mali drew 0-0 with Mexico in Group A, while Tunisia fought back to grab a 1-1 draw with Australia in Group C.

Australian striker John Aloisi put his team ahead in the final minute of the opening half, but Tunisia dominated the second half and were unfortunate not to win the game.

The African champions' equaliser came in the 69th minute through Esperance forward Ali Zitouni after Australian goalkeeper Eugene Galekovic failed to clear a high ball.

The ball was played back in from the right by substitute midfielder Mejdi Traoui for unmarked Zitouni to volley home from the edge of the six-yard box.

Olympic tables

The Tunisians continually pressed the Australia goal in the second half and were superior after being shaded in the opening half by the Australians.

The north Africans had a last-ditch chance to take all three points inside the final minute but Zitouni's shot flashed wide of the right upright with Galekovic beaten.

In a tame opening half, Australia had the better of the meagre chances on offer with midfielder Ahmad Elrich having a goal ruled out for offside after 26 minutes.

Yet the Australians broke through as half-time approached, when Aloisi headed past Tunisian goalkeeper Khaled Fadhel.

Tunisia's hopes of progressing past the first round for a first time will be largely determined by Saturday's encounter with tournament favourites Argentina, who thrashed Serbia and Montenegro 6-0 on Wednesday.

Meanwhile, Mali registered a goalless draw against Mexico on their Olympic football debut.

Striker Omar Bravo twice went close for Mexico and the African side had a lucky escape when Rafael Marquez missed an open target.

Yet Mali's Teneme Ndiaye could have gained a famous victory for his nation only to shoot wide of the target with just Mexican goalkeeper Jose Corona to beat.

In the other Group A game, hosts Greece fought from two goals down to draw 2-2 with South Korea.

On Thursday, both Morocco and Ghana open their Olympic campaigns.

The Moroccans take on Costa Rica in Heraklion in Group D, while 1992 bronze medallists Ghana face Italy in Volos in Group B.