The Carthage Eaglets cranked up the pressure on the Tajikistan goal late on and their persistence was rewarded when Msakni latched onto a corner kick to fire home a spectacular winner.
France took the lead just before half-time with a free-kick from Henri Saivet, but Nour Hadhria gave the Carthage Eaglets the equaliser four minutes after the break with a stunning 25-metre drive.
Even though Nigeria has since achieved further success at the Fifa under-17 World Cup in 1993 and 2007, the success of the 1985 Golden Eaglets remains a major milestone in the country.