Ivory Coast’s tie with Sudan leaves the African Champions with five points from three matches while Sudan are in second position with four points and Sierra Leone with just a point at the bottom of the table.
However, victory against Sudan and Ivory Coast in Sierra Leone’s final two matches could see them move at the top of the table and secure a place in the 2017 AFCON finals.
Tetteh, who does not want to give up hope of qualifying, said: “If we get the result we wanted there is no reason why we will not qualify.
“However, we must take it game by game, the Sudan match is a must win for us in Freetown and then we go for the Ivorians, who have struggled in the past to defeat Sierra Leone.”
Sierra Leone will host Sudan at the National Stadium in Freetown on 3 June before traveling to Ivory Coast on 2 September for what could be the group decider.