By Alex Capstick
BBC Sport, Cairo
Angola wasted a succession of chances as they were held to a goalless draw by DR Congo in a very physical and competitive Group B match in Cairo.
Kali shows his frustration after missing a chance
DR Congo's Tresor Mputo was sent-off after kicking Kali, who had earlier scuffed a great chance close to goal.
Angola striker Akwa forced two good saves from Pascal Kalemba, while a foul from Gladys Bokese on Flavio should have resulted in a penalty.
Lomana LuaLua missed clear goalscoring chances in each half for Congo.
The result means DR Congo have four points after their opening two African Cup of Nations games and are in a strong position to qualify from their group.
But Angola, who will be at the World Cup in Germany, must now win their last game against Togo and rely on other results if they are to advance.
Angolan coach Luis Goncalves, concerned after conceding three goals against Cameroon, made three changes to his defence.
His opposite number Claude LeRoy surprised nobody by naming an unchanged side.
In a frenetic opening period Angola's captain Akwa should have put his side ahead, but his sixth-minute strike was directed at DR Congo goalkeeper Kalemba.
At the other end LuaLua was causing problems for the Angolan defence, but with little end product.
The Portsmouth striker made a hash of a glorious opening with only Angola goalkeeper Ricardo to beat.
Flavio was equally wasteful for Angola, lifting his attempt over Kalemba but on to the roof of the net.
Moments later, and with the goal at his mercy, defender Kali shot wide at the far post.
It had been a difficult start for DR Congo, and the frustration was too much for Mputo.
All of his excellent work against Togo in their opening match was forgotten when he launched a wild kick between the legs of Kali in the 19th minute as the defender tried to shepherd the ball out of play.
Despite being down to 10 men DR Congo still carried a threat going forward and LuaLua might have given them the lead a few minutes before the break.
After a slow start to the second period Goncalves replaced Flavio with another striker, Maurito, and Macaba was given a chance in midfield at the expense of Mendonca.
The Angolans continued to pour forward but Akwa was unable to rekindle the scoring powers that had been so crucial in their successful World Cup qualifying campaign.
Angola continued to dominate possession but lacked a cutting edge - the Simbas able to contain their numerically superior opponents with growing ease.
DR Congo coach Claude Le Roy:
"I take my hat off to them. I find myself doing that a lot but for them to have held out for 70 minutes like that is a great achievement.
"Anything is still possible but we know that a draw with Cameroon will suffice. Cameroon are the strongest team but having seen what my players did....
"Perhaps Mputu paid a heavy price, but he will learn from it."
Angola midfielder Paulo Figueireido:
"We are disappointed because we believe we played well. However I still think we can make the last eight."
Angola coach Luis Oliveira Goncalves:
"We still have a chance and we are going to take it.
"African Cup games are very different from World Cup games. In Germany, we will do our best to make Africa proud."