President of the Ghana Football Association, Mr. Kwesi Nyantakyi has expressed his disappointment in the performance of the Black Stars in the last group game against the Syli Nationale of Guinea saying the encounter has taught the Black Stars a great lesson as they progress to the knockout stage of the 28th Africa Cup of Nations.He also did not mince words in saying that Wednesday's performance by the team was not convincing from a side heavily tipped to win the tournament.Speaking to Asempa sports on Thursday, he said the players need to work extra harder and redouble their efforts to be able to bring the gold home.The Black Stars management committee chairman held an emergency meeting with the team after the game, to motivate them and to tell them to buck up if they really want to lift the trophy.The president of the association however stated that, the entire team admitted the bash in good fate and promised a good show in the subsequent matches.Meanwhile, the players have been promised their qualification bonuses on Saturday as they face Tunisia in the quarter finals on Sunday.