Kennedy Gondwe BBC Sport, Chingola

Ryan Botha couldn't inspire South Africa to a win

Zambia have shot to the top of Group D in the Olympic qualifiers after beating South Africa 2-1.

A goal in each half saw Zambia back in the driving seat with seven points.

Yet the leadership is still under threat because Ghana and Algeria, the other countries in the group, play on Sunday in Kumasi.

Algeria are on six points while Ghana have four.

Zambia's first goal arrived in the 7th minute from Kaizer Chiefs' new signee Collins Mbesuma, who finished off an indirect free-kick taken by Noel Mwandila.

But South Africa equalised in the 12th minute through Mabhuti Khanyezi's header.

With only five minutes to the interval, South Africa seemed to have increased their tally via Ryan Botha.

However Malawian referee Youngson Chilinga disallowed the goal after the Turkey-based striker handled the ball before shooting.

Zambia's winning goal was scored in the 72nd minute from forward Jacob Mulenga who headed in a Songwe Chalwe cross.

But soon after Chilinda blew the final whistle, South African players, led by Panathanaikos striker Nassief Morris, invaded the pitch and man-handled the referee in protest against alleged biased officiating.

It was only after the intervention of the police that Chilinda was saved.

Zambia national team technical director Kalusha Bwalya urged the players to forget about the victory and concentrate on the next match against Algeria next month.

South Africa's coach Kenneh Kubheka, seemingly angered by the referee's officiating, refused to talk about the game.

Ikhana led Nigeria to a win in his first game

Meanwhile in Group A, Nigeria beat Senegal 2-0 to jump to the top of the table.

In front of a large crowd in Kano, Endurance Idahor did the damage, scoring twice in the second half.

Senegalese frustration was compounded when Abdoulaye Niane was sent off.

The victory confirmed a succesful first game in charge for Nigeria's new coach Khadiri Ikhana, the man who led Enyimba to Champions League glory in December.

Nigeria are now ahead of Senegal on goal difference.

Tunisia will go top of the group if they beat pointless Egypt on Sunday.