The sides will meet at the Sam Nujoma Stadium in Katutura, Windhoek (kick-off at 17h00), with the Super Falcons the favourites to progress after winning all three of their group games. Banyana picked up four points from their three matches, thumping Algeria 5-1 after drawing 1-1 with Ghana and losing 1-0 to Cameroon.
The top three finishers at the competition will qualify for the 2015 Women's World Cup in Canada.
Ellis, a former Banyana star, said: “It’s going to be a tough game - when we play Nigeria it is always tough. We know what’s at stake, not only a spot in the finals of the tournament, but we also want to book our spot in next year’s World Cup. It will be an exciting encounter, but very difficult as well.
“We have played them before in this tournament and did well, but now it’s a completely new game, at a new tournament so we will not dwell on the success we had over them in the past. We have to apply new tactics and new energy to do well but I am confident we can beat them.”
Ellis added: “Each and every team you play against, you plan for. Sometimes what you had planned does not work out the way you would want it to, and you just have to face the challenge ahead. We have played Nigeria before and I believe our team is ready, so we will give our very best.”