Liverpool star Sadio Mane was among the goals as Senegal cruised to a 4-1 win over Namibia on Saturday, and near-certain qualification for the final World Cup elimination round in Africa.
Another victory over the Namibians on Tuesday will seal first place in Group H for the Senegalese, who are chasing a second successive appearance at the global showpiece.
The convincing matchday 3 triumph in Thies near Dakar lifted Senegal to nine points while Namibia have four, Congo Brazzaville two and Togo one.
Namibia must face star-stacked Senegal a second time within four days at neutral Soweto on the outskirts of Johannesburg because they do not have an international-standard stadium.
Paris Saint-Germain midfielder Idrissa Gueye gave the Teranga Lions an early lead in Senegal that Turkey-based Famara Diedhiou increased before half-time.
After Mane claimed his third goal of the qualifying campaign on 55 minutes, Joslin Kamatuka pulled one goal back only for Keita Balde to restore the three-goal gap.
In Casablanca, Ayoub el Kaabi scored in each half as Morocco cantered to a 3-0 Group I win over Guinea-Bissau and, like Senegal, the north Africans can punch a ticket to the final round on Tuesday.
The Moroccans play Guinea in a rescheduled matchday 2 fixture in Rabat and victory will give the Atlas Lions an uncatchable eight-point lead as they chase a sixth World Cup appearance.
Pacesetters South Africa remain one point ahead of Ghana in Group G after both nations achieved 3-1 victories.
South Africa overcame third-placed Ethiopia in Bahir Dar while Ghana were too good for bottom side Zimbabwe in Cape Coast.
Captain and goalkeeper Ronwen Williams made several superb first-half saves for South Africa, who snatched the lead just before half-time through Teboho Mokoena.
- South Africa triumph -
Famed for his powerful shooting off set pieces, Mokoena seemed overly ambitious by aiming to score from a free-kick well outside the box, but goalkeeper Fasil Gebremichael spilled the ball into the net.
Another free-kick brought Ethiopia level midway into the second half with Getaneh Kebede exploiting poorly-positioned Williams as he rifled the ball into the net.
South Africa regained the lead within four minutes as a long throw was nodded on to Mothobi Mvala, who netted from close range.
Bafana Bafana (The Boys) clinched maximum points in the first minute of added time when substitute Evidence Makgopa broke clear and his lob over Gebremichael landed in the net.
South Africa have seven points, fellow three-time World Cup participants Ghana six, Ethiopia three and Zimbabwe one.
Zimbabwe faced Ghana after expressing unhappiness at the hard, uneven pitch with knee-high grass on which they had to practice.
Playing under Serbian coach Milovan Rajevac for the first time after Charles Akonnor was sacked following a loss in South Africa last month, Ghana led within five minutes through Mohammed Kudus.
Knowledge Musona equalised via an early second-half penalty only for Ghana to regain the lead through Arsenal midfielder Thomas Partey and long-serving Andre Ayew added a third goal near the end.
Rajevac has returned for a second spell in charge of Ghana having guided the Black Stars to second place in the 2010 Africa Cup of Nations and the quarter-finals of the World Cup the same year.