The 2013 Afcon winner is back in contention for Gernot Rohr’s side after recovering from a knee injury he suffered during Nigeria’s 2-0 defeat to Madagascar.
The Super Eagles captain took part in light training during the team’s recovery session on Sunday morning but has since stepped up his training regime.
Mikel missed the Round of 16 tie against Cameroon- with Odion Ighalo sending Nigeria into the last eight with a brace and the assist for Alex Iwobi’s winner.
But the 32-year-old is now available for selection, along with Shehu Abdullahi (hamstring), who was absent since the group match against Guinea.
South Africa will be looking for their first win over Nigeria in Afcon finals history, while the Super Eagles will be looking to continue on the road to what will be their fourth continental crown.