Substitute forward Kelechi Iheanacho and goalkeeper Stanley Nwabali played key roles as Nigeria beat South Africa 4-2 on penalties on Wednesday in an Africa Cup of Nations semi-final thriller.
The three-time champions will face hosts Ivory Coast, who dominated the Democratic Republic of Congo but had to settle for a 1-0 win in Abidjan, in the final on Sunday.
Nigeria triumphed after a 1-1 draw following extra time in Bouake in the latest of many dramatic matches at this biennial African football showpiece.
"Our team has a huge state of mind. The team fights together, There are 25 of us (in the squad and) it's difficult to beat us," said Nigeria coach Jose Peseiro.
"Deep down, thinking about that second cancelled (Nigerian) goal and the (South African equaliser), a lot of teams would have given up.
"I am very happy, the players are happy, they deserve it, we deserve it, the Super Eagles deserve it, the Nigerian people deserve it."
South Africa coach Hugo Broos said: "Football can be cruel. You play a bad match against Cape Verde, you win on penalties. You play a very good match against Nigeria and lose on penalties."
Iheanacho from English second-tier club Leicester City had been an unused substitute in the five group and knockout matches that took the Super Eagles to the semi-finals.
He was thrust into action by Portuguese Peseiro for the first time after 102 minutes against South Africa and calmly converted the decisive spot-kick.
Nwabali, who plays for South African top-flight club Chippa United, saved shootout kicks from Teboho Mokoena and Evidence Makgopa.
Peseiro, a long-time backer of under-fire incumbent shot-stopper Francis Uzoho, dropped him for the opening group match against Equatorial Guinea and Nwabali has been an ever present.
Nwabali conceded once in a draw with the Equatoguineans, then kept four clean sheets before being beaten by a Mokoena penalty in the 90th minute of regular time.
Nigeria had taken the lead 23 minutes earlier, also from a penalty, which captain William Troost-Ekong converted.
Khuliso Mudau had a great chance to win the match for South Africa just before extra time, but blazed over from close range.
South Africa captain and goalkeeper Ronwen Williams, who saved four kicks in a quarter-final shootout win over Cape Verde, could not stop a single kick.
Before Iheanacho netted, fellow substitutes Terem Moffi and Kenneth Omeruo and Troost-Ekong converted penalties and Ola Aina blazed over.
In an absorbing match watched by a 32,000 crowd, Nigeria thought they had taken a two-goal lead on 85 minutes when star forward Victor Osimhen scored.
But play was called back to the other end and, after the Egyptian referee checked the pitchside VAR monitor, he awarded South Africa the penalty that Mokoena netted.
Reigning African Player of the Year Osimhen, who started the match after recovering from abdominal discomfort, was substituted in extra time after another tireless performance.
South Africa played the final seven minutes with 10 men after Grant Kekana was shown a straight red card for a last-defender foul on Moffi.
The win sparked celebrations back in Nigeria.
"For a first time for a long time we are excited, we are happy Nigeria beat South Africa," supporter Peace Nwanro said in Lagos. "Nigeria will keep winning."
It will be the eighth final appearance by Nigeria, who were champions in 1980, 1994 and 2013, and the fourth by 1992 and 2015 title winners Ivory Coast.
Later, after the seesaw struggle for supremacy in Bouake, the Ivory Coast continued a remarkable comeback in the tournament by defeating DR Congo.
Sebastien Haller was the 65th-minute match-winner as his boot connected with a cross and the ball struck the ground, then rose over goalkeeper Lionel Mpasi and into the net.
Haller had missed the group stage through injury before making his first appearance in a shock last-16 victory over Senegal.
After a humiliating 4-0 thrashing by Equatorial Guinea in the group stage, the Ivorians squeezed into the knockout phase as the last of the four third-placed teams who qualified.
But the embarrassment of a record home loss to the Equatoguineans was forgotten as Franck Kessie was denied by the woodwork and Haller missed a great chance before becoming the hero.
