Nigeria coach Gernot Rohr is wary about fatigue affecting the home-based Super Eagles in their African Nations Championship semi final with Sudan on Wednesday.
Salisu Yusuf's side came from behind to beat Angola 2-1 in their quarter final at the weekend to set up a showdown with a Falcons of Jediane team who held hosts and favourites Morocco in the group stage before seeing off Zambia in their last-eight clash.
While Nigeria were forced to play 120 minutes against Angola in their game in Tanger on Sunday, Sudan got the job done in 90 minutes against Chipolopolo and, having played on Saturday, may enter Wednesday's showdown more refreshed than the Super Eagles.
"[It] will be very, very difficult because they've had an extra day of rest," Nigeria's senior-team coach Rohr told KweséESPN. "They played [on Saturday] and didn't have extra time, we did.
"We have one day less for recovery, but I think physically we are ok," he continued, "and we can win also the semi final.
"This time we'll try to win before the extra time, so that we don't lose too much energy for the final."
Yusuf is also contending with a litany of injury problems ahead of the final-four clash, with bright forward Sunday Faleye - ruled out of the tournament with an elbow injury - one of a handful of casualties.
Left-back Daniel Itodo will also miss out, meaning youngster Ikouwem Utin will continue to deputise, while Ifeanyi Ifeanyi is still struggling with a groin problem.
"We have injuries, at least two," added Rohr. "[Faleye] injured his elbow and then there's another [injury] which will prevent the kid from playing.
"However, the morale in the team is good. Physically, Nigeria are often excellent players at this stage"
Finally, Rohr expressed some concern that Sudan may have the edge in terms of experience and big-game nous.
While only goalkeeper Ikechukwu Ezenwa is a regular in the Super Eagles set up from the team present in Morocco, Sudan boast essentially their full senior side with none of the nation's major players based outside their domestic top flight.
"All of the [Nigeria] team deserved qualification," Rohr concluded, "but the semi final will be difficult because you have to play against a team who already played yesterday.
"Sudan have their A team here - the same side - so it will be very difficult."
Nigeria and Sudan meet in Marrakech in the day's second semi final at 19:30 local time, with Morocco and Libya clashing in a North African derby in Casablanca at 16:30.