Super Eagles were forced to 1-1 draw by their Egyptian opponents, the Pharaohs, in Friday's Africa Cup of Nations Afcon ) double-header first-leg clash at the Ahmadu Bello Stadium in Kaduna.
Attacking midfielder Oghenekaro Etebo put Nigeria in front in the 60th minute while Muhammed Salah scored at the death to hand the North Africans a crucial away point.
Chukwu said the Eagles were careless in the dying minutes, allowing the Egyptians the luxury of an equaliser.
"It was a sad result to finish the match at 1-1 against Egypt with few minutes remaining to play in the key Afcon clash.
"I think the defenders suffered a momentary loss of concentration at a time they should have been 100 percent alert.
"The Egyptians were more tactical throughout the duration of the match while we appeared to be under intense pressure to conjure a victory.
"Well let us see what happens in the reverse fixture clash next Tuesday in Alexandria.
"It will not be an easy game, but Egypt will be under pressure to win and that will likely open up the match, which we can use to get the all-important win.
"The game and contest for the group's qualification ticket is still wide open among the contending countries, Egypt, Nigeria and now suddenly Tanzania as well..
"We must strengthen ourselves to go for the broke, throw in everything into the match at Alexandria and chance winning right there at in their backyard.
"Egypt are quite beatable in Alexandria but we must be prepared to do what is needed, " said the former Nigerian strongman to supersport.com.
The score draw still leaves Nigeria on five points, two behind Egypt heading into the reverse fixture clash on Tuesday at the Borg El-Arab Stadium in Alexandria, Egypt.
The group's winners are guaranteed an automatic spot at the Afcon final in Gabon.