Although, the South Africans revenged their 2018 title loss at the Aisha Buhari Cup, where they defeated the Super Falcons 4-2 to lift the crown, Ellis insists the upcoming group stage meeting will be a 'very difficult game'.
"Well we always knew the draw was not going to be easy. Nigeria, the defending champions and multiple winners always bring their A game and know what it takes to win," Ellis told CAFOnline.com.
"We have played them a few times in the group stages. They have raised their levels and we have to raise our levels even higher to get a positive result. The first game is the most important game and once again we need a positive result but it will take a huge effort.
"Anything that has come before is history but it has shown us what we are capable of and has given us confidence and belief. As I said earlier we have played them many times in the group stages and this will be no different especially with this being an opening group match which is similar to 2018.
"We will need a huge effort to get a positive result. The first game is the most important of any tournament and getting a positive result is very important but we know that it’s not going to be an easy game. Actually, it’s going to be a very difficult game."
Besides Nigeria, the four-time WAFCON finalists will also battle debutants and COSAFA rivals Botswana, who ruined their Tokyo 2020 dream but Ellis insists her side will not be seeking any revenge against the Mares.