Burkina Faso are chasing the victory they know will give them a place in the quarterfinals of the 2017 African Nations Cup when they face minnows Guinea-Bissau in their final Group A clash in Franceville on Sunday.

The Burkinabe have played to a pair of 1-1 draws so far against Cameroon and hosts Gabon, but now, on paper at least, have their easiest fixture in the pool and will be favourites to earn a spot in the next round.

This even as they overcome twin injury blows to key men Jonathan Pitroipa and Jonathan Zongo, who are unable to continue in the tournament.

Pitroipa's injury is a major headache for the Burkinabe. He was voted the best player at the 2013 Nations Cup finals in South Africa but a muscle tear has ended his participation as he faces three weeks on the sidelines.

Zongo ruptured a cruciate ligament and left Gabon to Barcelona for surgery, likely out for up to seven months.

Burkina Faso coach Paulo Duarte said it was a major blow but called the injuries "unlucky and part of football" when asked about whether pitch conditions at the tournament were to blame.

The Burkinabe players have been talking their game up as a "final" and a must-win fixture, even though a draw could be enough to advance if Cameroon beat Gabon in the other pool match.

The hero of their 1-1 draw with the home side, Préjuce Nakoulma, says his team will not take a cautious approach.

"All teams still have a chance. The last game we must win," he said.

A draw could be enough but will depend on Gabon getting no more than a point against Cameroon, as well as Burkina Faso scoring more goals in a stalemate against Guinea-Bissau.

At the moment Gabon and Burkina Faso have identical records in terms of points, and goals scored and conceded, while the fixture between them finished 1-1.

It means the prospect of the drawing of lots looms, as it did in Equatorial Guinea in 2015 when the method was needed to separate Mali and Guinea.

Guinea-Bissau have entertained at these finals and are still in with a chance of making the quarterfinals if they beat Burkina Faso and Gabon get no more than a point against Cameroon.

Coach Baciro Cande says his team have done themselves proud so far and that they will fight to the end.

"We have to work hard against Burkina Faso and I am not really thinking about being knocked out," he said. "I have told my players we will play to the end and what we want is positive results - we we have learned important lessons on how to defend when you are leading."