Rasheedat Ajibade and Anam Imo's first-half strikes saw Basetsana bow to the Falconets 2-0 at the Old Peter Mokaba Stadium, leaving the hosts' World Cup dreams in the balance.
"I don't feel they (Nigeria) dominated us because they were only using long balls with advantage of the height, hence there was nothing like they had a better build up," Khumalo told media.
"They resorted to playing their long balls and making the switches well in the final third to get their goals.
"We managed to contain them in many moments of their one-two occasions but our final balls were the areas that let us down. As a coach, we must go back to the drawing board and look at the what went wrong in this game.
"They got their chances and made good use of it and for me, definitely, we might change and may not but I think everything is about the mental strength at the end of the day.
"The fear of meeting Nigeria did not affect us in any way because we knew we were going to meet them. The only thing that is important in a game is that you score goals whenever there is a chance. That is what they got theirs and made use of it.
Despite their slump at home in Polokwane, Khumalo is confident her side's mental toughness can help them overturn the two-goal deficit in Benin City.
"We are going to give our best, go all out and we need to fight till the end because there is no turning back. It is a pity that we conceded goals at home which was not our dreams coming into the game.
"But since when they have got those two goals, we need to see when we get to their side [Benin City] that we do it too. They only got those goals in the first half and could not come out against us in the second half because just they parked the bus. I think that was what they were waiting for.
"We are the same but they are more experience because of playing at the World Cup. I am happy with the performance of the girls despite we couldn't get those goals and prevent them from scoring. We also needed to play so that we can score.
"We are going to Nigeria knowing that we are two goals down. But we won't sit back and keep on playing our game and give our best to get those goals," she concluded.
Basetsana will be hoping to turn the table around in the second leg at the Samuel Ogbemudia Stadium on January 27.
The winner on aggregate will secure one of the two tickets as African representatives for the finals scheduled to hold from August 5-24.