"Lionel Messi is not a stranger to me because I was in Nigeria's Under-23 team that played in the final against Argentina in the 2008 Olympics," Ambrose told Goal.com.
"I also played against him in our friendly match in Bangladesh last year. So he won't pose many problems to me because I will do my best in marking him out when Celtic and Barcelona slug it out in the Champions League.
"I have also told Emenike that he should watch out for me because I will give him a serious challenge when our teams meet."
Ambrose joined Celtic from Israeli side Ashdod on transfer deadline day.