ABIDJAN :Nigeria booked their passage into the last 16 of the Africa Cup of Nations after a first-half own goal from Guinea-Bissau's Opa Sangante handed them a 1-0 victory on Monday, which was enough to earn them second place in Group A.Moses Simon sent in a low cross from the left looking for Victor Osimhen but as Sangante attempted to clear ahead of the striker he could only steer the ball into the roof of his own net after 36 minutes.Nigeria finish on seven points from three games, behind surprise package Equatorial Guinea on goal difference.Hosts Ivory Coast face an anxious wait to see if they will advance as one of the best third-place finishers with three points and a minus three goal difference.Nigeria dominated the game but poor finishing meant it was a tense encounter to the end, with Osimhen missing several chances to secure the three points earlier in the contest and both teams having late goals correctly ruled out for offside.Nigeria will be pleased with back-to-back wins after a limp start in their pool opener against Equatorial Guinea but there is still work for coach Jose Peseiro to do to get them fully firing.On paper they have among the best attacks in the tournament, but three goals in as many games is a poor return and this clash with Guinea-Bissau illustrated their troubles.They were wasteful in front of goal and at times looked disjointed as they battled to find cohesion in the final third of the pitch.They had been trying to create clear-cut chances until they were handed a gift in the form of Sangante’s own goal, before Osimhen should have made it 2-0 when left unmarked in the box but he steered his header wide of the post.