Chanchung Yatai dropped to the second tier of football in China after they lost 2-0 to Dalian Yifang away from home.
Ighalo was unable to feature in the encounter as he suffered a serious injury in their last fixtureagainst Tianjin Quanjin on Wednesday, November 7.
Sheng Qin set up Duvier Riascos in the 23rd minute and former Atletico Madrid star Yannick Ferreira-Carrasco in the 64th minute to seal a home win for Dalian Yifang against Ighalo's side.
Chanchung Yatai could not depend on their reliable striker Ighalo who has 21 goals this season in the league.
The result meant that Ighalo's Chanchung Yatai stayed on 32 points but Super Eagles as his Tianjin TEDA side also lost 5-1 to Guangzhou Evergrande.
The result meant that Tianjin Teda and Chanchung Yatai both have 32 points but Mikel's side scaled through in 14th position with a superior goal difference.
Ighalo's Chanchung Yatai and bottom placed Guizhou Hengfeng were both relegated from the first division.