Ambrose and his Nigeria team-mates will face Burkina Faso on Sunday evening at 1800 GMT, placing a question mark over his availability for the first leg of the last-16 clash at Parkhead.
Lennon concedes the versatile defender is a doubt but will give him every opportunity ahead of Tuesday's European outing.
He told CelticTV: "Nigeria did fantastically well and Efe has played brilliantly in the game so I'm delighted for him in one way, but obviously very frustrated in another.
"The final is on Sunday and he probably won't get back until Monday evening, so he would be a doubt.
"We will get him into the squad and see how he is feeling."