Sudan kept their 2012 Africa Cup of Nations hopes on track with a hard-fought 2-1 victory over Swaziland in Mbabane on Sunday.
The result kept up the pressure on Group I leaders Ghana who stay top on goal difference.
Ghana had opened a three-point advantage following their 3-1 win over ten-man Congo in Kumasi on Friday.
Second-half goals by Isaac Vorsah, Prince Tagoe and Emmanuel Agyemang-Badu sealed the victory for the Black Stars.
Congo got the consolation through striker Matt Moussilou.
The Congolese were undone by the dismissal of key defender Bruce Abdoulaye for a second bookable.
Michael Essien marked his international return from an 18-month absence by playing a leading role in the win.
The Chelsea midfielder, back for the first time since the 2010 finals after ending a self-imposed exile, set up an early chance with a rasping shot that the visiting goalkeeper spilled.
Ghana struck two quickfire goals midway through the second half thanks to Vorsah and Tagoe.
Moussilou took advantage of a mistake by goalkeeper Richard Kingson to pull a goal back for Congo with 15 minutes left but Agyemang-Badu made it 3-1 to Ghana with a long-range shot.
Second from bottom Congo, who have three points, can no longer qualify.