Martins is expected in Tunisia on Thursday

An NFA spokesman said the Italian club has written to them advising that they will release Martins 48 hours before the match against Tunisia.

The player himself has apparently given his word to the NFA secretary-general that he will be in Tunisia for the match.

The 19-year-old forward has so far turned down the chance to play for his native country.

But the news that he will be part of the team for Saturday's decisive Olympic qualifier will be a massive boost to Nigeria who will be without several other established internationals.

France-based John Utaka will not be released by his club RC Lens while Emmanuel Okoduwa, who features for Arsenal Kiev, has also been told not to go by the Ukrainian team.

Everton's 23-year-old defender Joseph Yobo is not eligible to play for the 1996 Olympic football champions.

Only players under the age of 23 can play in the qualifiers, although teams are allowed to field three over-aged players in the tournament at the Games.

Nigeria lead Group A with 10 points from five matches. A draw against closest rivals Tunisia will earn them a ticket to the Athens Olympics in August.