Sudan, ranked 110th in the world, were third seeds in their group when the 2025 Afcon qualifying draw was made in July.
However, taking four points from a double-header against four-time Nations Cup winners Ghana last month put the team, which is coached by former Black Stars player and manager Kwesi Appiah, a point away from reaching the finals.
Appiah’s side fell to a damaging 4-0 defeat away against Niger last week, but Eisa said the squad remained positive heading into their final game against already-qualified Angola on Monday.
“The Niger game took us by surprise,” the 28-year-old, who plays his club football in Thailand, explained.
“On the way home, we said to ourselves we’re more than capable. We knew we had pressure, but at the same time we knew we could get the job done.”
Sudan ground out a 0-0 draw in Benghazi, at their makeshift home stadium, to seal second spot in Group F.
Eisa said the side have fed off the support of the Sudanese diaspora in their two qualifiers hosted in Libya – as well as local supporters – after starting their campaign in South Sudan.
“We’ve had a really big following,” he added.
“Obviously it’s not home, it’s not Sudan, but at the same time it does feel like that with the support that they show and bring to us.
“[Against Angola it] was very loud. We couldn’t hear ourselves.”