Guinea-Bissau missed a late penalty as they were held by Sudan in their Group D opener in the Africa Cup of Nations.
Midfielder Pele saw his 82nd-minute spot-kick kept out by Sudan goalkeeper Ali Abou Achrine, with Piqueti striking the bar on the rebound.
Abou Achrine had been adjudged to have fouled Steve Ambri inside the area.
Guinea-Bissau’s Joseph Mendes also hit the post with a first-half header and Frederic Mendy saw an effort cleared off the line late on.
Earlier in Group D Kelechi Iheanacho was on target as Nigeria comfortably beat seven-time champions Egypt.
The result means Guinea-Bissau have failed to score in each of their past five Nations Cup matches and now face an uphill battle to reach the knockout stage for the first time.
Elsewhere, Kelechi Iheanacho was on target as Nigeria comfortably beat seven-time champions Egypt in their Africa Cup of Nations Group D opener.
The Leicester City striker opened the scoring in the 30th minute, burying a stunning half-volley on the turn.
The Pharaohs offered little in response after falling behind in Garoua.
Sudan will face Nigeria while Guinea-Bissau take on Egypt on Saturday.