South Africa and Nigeria are both regarded as regional 'giants' having real or perceived capacity to play strategic roles in Africa's political-economic settings. On one hand, South Africa's dominance in Africa's political-economic transformation since 1994 is reflected mostly in its business expansion in Africa. Nigeria, on the other hand, remains significant having only just been upstaged by South Africa as Africa's largest economy, and with the huge market its population provides for investors. Notwithstanding intermittent diplomatic altercations between both countries, there has been rising trade and investment relations between the two regional powers especially since the post-apartheid era. However, this is tilted in favour of South Africa because of its more capitalized economy and significant strength in trade investment in Africa. This skewed economic relationship between both regional powers has given South Africa a major trade and investment advantage over Nigeria which also reflects in the recurring political rivalry between both countries. The authors stress that South Africa's economic incursion and dominance in the continent furthers a growing perception of its regional hegemonic and sub-imperial power aspirations which is becoming more real than imagined.