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By Mark Gleeson
LIBREVILLE, Jan 18 (Reuters) - Hosts Gabon's continued participation in the African Nations Cup was in serious doubt after they were held 1-1 by Burkina Faso on Wednesday, their second draw in Group A.
Pierre-Emerick Aubameyang again scored for his country but they had to come from behind to equalise and missed two good late chances to win the game.
Gabon and Burkina Faso have two points each from their opening two matches, with Cameroon due to play Guinea Bissau later on Wednesday.
Prejuce Nakoulma put Burkina Faso ahead in the 22nd minute before Aubameyang equalised through a penalty.
Substitute Nakoulma, who had come on early when Burkina striker Jonathan Pitroipa appeared to suffer a serious knee injury, ran from the edge of his own penalty area on to a defensive clearance and got the better of full back Johan Obiang before gliding the ball into the net.
Burkina Faso's lead lasted 16 minutes when they were caught in similar circumstances as a long ball from Merlin Tandjigora was chased down by Aubameyang, who had his feet taken out from under him by goalkeeper Herve Koffi. The resultant penalty was neatly tucked away to the relief of the home crowd.
But Gabon offered little evidence of being serious contenders at their own tournament until the last 10 minutes when Denis Bouanga had a close-range effort well saved by Koffi and Serge Kevyn missed with a header.
Gabon were without injured defender Mario Lemina and lost another defender Johann Obiang to injury in the first half.
Pitroipa's early departure could be a serious setback to the Burkinabe in their quest to repeat the heroics of 2013 when they got to the Nations Cup final and the forward was named player of the tournament.
Gabon's poor start was also reflected in a far from full stadium in the country's capital for the key game as sceptical supporters stayed away. (Editing by Ed Osmond)