K'Ogalo defeated the Nigerian side Lobi Stars 3-1 on Sunday at Kasarani in the first leg of the final preliminary round and will need just a draw in the second leg to progress to the Group Stages.
Oktay says that self-belief was the main reason that pushed his team to record an impressive result against the West Africans.
"It is ninety percent done; we are close to progression, but we have to finish the job away. We understand it will not be a walk in the park, but with the quality we have here, it is possible. Everyone was impressive on Sunday and gave everything, and that is the attitude we want away.
"Belief is what we needed to get the result, minus it, things could have been a bit hard and maybe we could not have registered the result," Oktay told Goal.com.
Gor Mahia goals were scored by Samuel Onyango, who hit a brace, and Rwandan international Jacques Tuyisenge.