Nigeria were among seven countries to build first-leg leads while keeping clean sheets in 2016 African Nations Championship (Chan) qualifying this weekend.
Angola, Burundi, Guinea, Niger, Uganda and Zambia also established aggregate advantages ahead of return matches next weekend in the biennial competition restricted to home-based players.
A further five first legs are scheduled for Sunday and all the overall winners secure places at a 16-nation tournament in Rwanda next January and February.
Having qualified for the first time last year and finished third, Nigeria look set to return next year after building a 2-0 lead over Burkina Faso in south-east city Port Harcourt.
Bature Yaro slammed the ball into the net midway through the opening half and Gbolahan Salami sent goalkeeper Mohammed Bailou the wrong way from a late second-half penalty kick.
Uganda, seeking a third consecutive Chan tournament appearance, overcame Sudan 2-0 in Kampala despite having a player red-carded and conceding a penalty .
Frank Kalanda and Farouk Miya scored before Hassan Dazo was sent off and James Alitho saved a Mudather Eltaib spot-kick.
Zambia were the most impressive winners, defeating Mozambique 3-0 in Ndola after taking a long time to break down the visitors.
Winston Kalengo broke the deadlock on 77 minutes, Conlyde Luchanga doubled the lead soon after and Spencer Sautu struck in the final minute.
Angola are another country looking good for a place in Rwanda after leaving Johannesburg with a 2-0 lead over a makeshift South Africa side.
A deflected Mateus Da Costa shot that looped over goalkeeper Wayne Sandilands soon after halftime and a stoppage-time Manuel Afonso goal secured success for the visitors.
But the refusal of clubs to release stars because the games are not staged on Fifa-sanctioned dates meant South Africa fielded footballers who cannot command regular starting places at their first and second-tier clubs.
Guinea moved closer to a first finals appearance by overcoming Senegal 2-0 in a game switched from Conakry to Malian capital Bamako because of the Ebola epidemic.
Aboubacar Mouctar Sylla scored just five minutes after the kick-off and Aboubacar Iyanga Sylla increased the lead midway through the opening half.
Niger were another team to inflict early damage with both goals in a 2-0 victory over Togo in Niamey coming within the first 14 minutes.
Idrissa Halidou broke the deadlock and Koffi Dan Kakowa also struck for the Nigeriens.
Early and late Laurent Mavugo goals earned Burundi a 2-0 win over Ethiopia in Bujumbura and a realistic chance of qualifying for a second successive tournament.
Title-holders Libya are involved in a mini-league including Tunisia and Morocco that resumes next week near Tunis with two finals places up for grabs.
Democratic Republic of Congo, winners of the maiden African Nations Championship in 2009, booked a finals place after cash-strapped opponents Central African Republic withdrew.