Bafana face a stiff ask in making it to Russia 2018 as two shock losses to Cape Verde last month left them bottom of Group D with a point from three games.
Stuart Baxter's side initially beat Senegal in an earlier qualifier but FIFA ordered a replay in November after referee Joseph Lamptey was found guilty of match-fixing.
Bafana on Saturday host pool leaders Burkina Faso at FNB Stadium before concluding their campaign with back-to-back matches against the Teranga Lions.
"To be quite honest we are in trouble," Manyama told SAFA Media.
"We put ourselves in there and we are the only ones who can take ourselves out. It’s up to us to get a good result on Saturday before we can think of anything else. We know its not going to be easy, but I think we have a lot of quality in the side. It’s a matter of doing what the coach wants – it has worked before so why cant it work on Saturday?
The Turkey-based forward appealed for the nation's support on the weekend.
"We know what has happened in the last two games and people have lost confidence in us but we must take the lead to bring back the confidence and everybody else will follow. We need their support. We have the quality, we have the coach and I believe we have the country that can take us where we want to go, starting on Saturday.
"Like I always say, all for one and one for all. We need the whole nation. If we can have a packed stadium whenever you touch the ball it builds confidence and in a way everything goes right when you have fans behind you. I think we are going to need them more than ever, so come show your love for Bafana Bafana," concluded the former Cape Town City captain.