The Super Eagles Secure Africa Cup of Nations Knockout Place Despite Late Carthage Eagles Comeback
Former Continent's Best Player of the Year the Napoli star helped Nigeria build a commanding advantage, before they were forced to defend resolutely for a hard-fought win.
Nigeria weathered a dramatic late rally from Tunisia to progress to the last 16 of the Afcon tournament taking place in the host nation.
Jose Peseiro's side seemed to be cruising in their pool clash in Fes, enjoying a 3-0 cushion with only a quarter of an hour remaining thanks to strikes from their attacking trio.
However, Montassar Talbi pulled one back with a powerful header from a Manchester United midfielder set-piece, sparking hopes of a turnaround.
The drama escalated when the North Africans were given a spot-kick after a video assistant referee check identified a handball by Bright Osayi-Samuel. The left-back calmly slotted home in the 87th minute to set up a frantic finale.
Tunisia were inches away from a stunning leveler in added time, with their skipper directing a chance just past the post before a substitute guided a bobbling volley past the upright.
Clinching Top Spot
The victory means that Nigeria, champions of the competition on three past instances, advance to 6 points and are guaranteed first place in their pool with one game left to play.
In the next round, they will meet a best third-place team from either Group A, B or F.
In the other match, Tunisia remain on 3 group points, with the East African teams tied on a single point each after playing out a 1-1 stalemate earlier on Saturday.
The concluding group matches will see Nigeria stay in the city to play Uganda on the next matchday, while Tunisia travel back to Rabat to face the Taifa Stars.
A Nervy Finish
Ali Abdi smashed the ball from the penalty spot to offer his team hope of snatching a point.
The Super Eagles, runners-up in the previous tournament, become the second team after the Pharaohs to reach the next phase, but coach Eric Chelle and fans will certainly be breathing a sigh of relief.
What seemed set to be a straightforward final quarter morphed into a nerve-wracking conclusion.
The prolific striker had a effort disallowed for an infringement before opening the scoring right before half-time, expertly guiding a glancing effort into the bottom corner from an Atalanta winger cross.
The advantage was doubled soon in the second half when the Leicester City midfielder climbed above everyone to thump in a powerful nod from a Lookman kick.
Osimhen then set up his teammate for the third goal, only for the defender to steer a powerful header past goalkeeper Stanley Nwabali to initiate the fightback.
The key moment arrived when a looping cross struck the arm of Bright Osayi-Samuel, with referee Boubou Traore awarding a penalty after reviewing the pitchside screen.
Although the defender's confident conversion, Tunisia ultimately came up just short of pulling off a remarkable recovery.
Tunisia's destiny is still in their own hands; a point against Tunisia will be sufficient to secure progression, and manager Sami Trabelsi will be eager to prevent a repeat of the past group-stage exit that led to his departure.