Nigeria lose Yobo for two weeks
"The result of the scan is that Yobo will be out for two weeks. He has rejoined the team, but he is very unlikely to take any further part in the Nations Cup," said Nigeria Football Federation (NFF) official Taiwo Ogunjobi.
Yobo tore his hamstring as he tackled Benin striker Razak Omotoyossi early in the second half of their Group C match in Benguela.
Nice defender Onyekachi Apam replaced Yobo in Wednesday's 3-0 victory over Mozambique, which qualified Nigeria for the quarter-finals of the tournament.