Ighalo lifted his shirt to reveal a message that and was instantly booked by Egyptian referee Ghead Grisha after netting the opening goal in the Super Eagles' 4-0 victory over Cameroon in Uyo on Friday.

"He told me that the message on my shirt was about religion because it's 'thank you Jesus'," Ighalo told KweséESPN.

Displaying unsanctioned commercial, political, religious or personal slogans or statements in undershirts are outlawed by FIFA and subject to additional sanction, mainly fines.

The most recent incident of a similar violation is Qatar, who warmed up for their World Cup qualifier against South Korea in June wearing T-shirts with the picture of Emir Sheikh Tamim bin Hamad Al Thani to show their support after several Gulf nations and Egypt cut ties with Qatar and imposed economic sanctions on Doha for allegedly supporting "extremism".

Referee Grisha is expected to include the incident in his report for further action by FIFA. Ighalo, who hobbled off with an ice pack after a barnstorming performance in Nigeria's 4-0 destruction of Cameroon, has assured KweséESPN that the injury is nothing serious.

"It was just a tight hamstring, but I am fine now," Ighalo said.

That will be cause for a collective breath of relief across the country as the Super Eagles prepare to face Cameroon in the second of the twin fixtures on Monday.