This follows his side’s failure to win any of their opening two qualifying matches against Angola and Niger this month.
The Black Stars fell to a shocking 0-1 home defeat at the hands of Angola last Thursday and were also held to a 1-1 draw by Niger on Monday.
Ghana’s next qualifying game will be a double-header against Sudan, who are managed by Ghanaian coach James Kwasi Appiah, in October.
Otto Addo targets redemption against Sudan
Addo believes the games against the Secretarybirds will be difficult and has also admitted that the Black Stars are under pressure.
“It will be difficult again. I knew from the start, it's just some little margins, little details which can decide. This will be again, for us it will be a crucial match,” the 49-year-old said, as quoted by GhanaFA.org.
“We have to win, there is no way around it, and we have to win. If we want to have the chance to play better after, we have to win. We are under pressure, this is for sure and we have to do better.”
Addo was, however, quick to add that the Black Stars’ chances of qualifying for the next AFCON were far from over.
He noted that the team needed to improve on their defence and learn their lessons from the two matches against Angola and Niger.
“So it's still possible but we have to improve, we have to improve much. We have to improve to use our chances and also to defend better in detail and to learn our lessons.
“Like I said, the goals are too cheap and we have to grow from this we have to learn from this. This is even more than a wake-up call,” the Ghana coach added.
Meanwhile, Addo has led the Black Stars to just two wins in six matches since being reappointed as the team’s head coach.