Liberia, Ethiopia and Tanzania all dug deep to book a place in the group phase of the 2022 World Cup Qualifiers.
Liberia had 18-year-old goalkeeper Ashley Williams to thank on Sunday after he saved a stoppage-time penalty in Sierra Leone to put his country through.
Sierra Leone was leading by a solitary goal to reduce their first leg 3-1 loss and the late penalty was all they needed to progress via the away goal rule but when their skipper Umaru Bangura stepped up in front of an expectant crowd at Free Town, Williams produced a dramatic save to deny them a chance.
Equatorial Guinea also advanced on Sunday, beating South Sudan 1-0 courtesy of an Emilio Nsue goal. The first leg had ended 0-0.
In the earlier matches on Sunday, Tanzania beat Burundi on penalties and Ethiopia were away-goals winners over Lesotho.
The 14 teams who advance from this round will enter the group stage, where they will join the 26 top-ranked sides in the 40-team, 10-group second phase.
Five places have been reserved for Africa at the 2022 World Cup in Qatar.