Nigeria bounced back from their opening defeat by Croatia by putting Iceland to the sword in Volgograd, winning 2-0 to revive their hopes of reaching the Last 16.
Ahmed Musa stole the show after being introduced to the side by Gernot Rohr, with the European side having no answer to his speed, movement and direct running as the Leicester City man netted twice.
Gylfi Sigurdsson also missed a late penalty as Iceland failed to stage a late comeback.
This was a big improvement from Nigeria after their underwhelming opener; they improved in possession and counter attacked superbly for the opening goal.
Musa's pace and movement, alongside Victor Moses on the other flank, proved too much for a staid Iceland defence whose creaking limbs were exposed here.
Defensively, Nigeria were compact, resilient and well organised, with the introduction of Kenneth Omeruo adding stability.
Francis Uzoho continues to grow game on game, and Nigeria were much improved defending set pieces.
The second-half display was a refreshing change from an underwhelming first 45 minutes.
The Eagles became the first side not to manage a shot in the first half of a World Cup game since South Korea and Algeria met in 2014, and it was all still too lethargic.
The team's decision-making in the final third also left a lot to be desired at times.
Manager rating (out of 10):
8 - Gernot Rohr opted for a tactical and personnel reshuffle after the defeat by Croatia, choosing three central defenders and introducing Musa, Omeruo and Kelechi Iheanacho.
Alex Iwobi was the most notable exclusion, and the Super Eagles did lack a link between the midfield and attack during the early stages.
However, Omeruo and, particularly, Musa justified their inclusion with superb showings.
The work on the training ground has clearly paid off with a better defensive shape and improved defending from set pieces, while Rohr also deserves credit for whatever he said at half time, which sent his team out with renewed spirit and ambition.
Player ratings (1-10, with 10 the best. Players introduced after 70 minutes get no rating):
GK Francis Uzoho, 8 -- Appeared confident from the off, palming a Gylfi Sigurdsson free kick wide before coming boldly to claim the resulting corner. His handling was excellent, and he appeared much more composed during set-piece situations.
DF Kenneth Omeruo, 8 -- Tarnished an otherwise excellent and mature display by giving away a penalty to allow Iceland back into the game, and watched on in relief as Sigurdsson fired over.
Justified his return to the side and created two goalscoring opportunities.
DF William Troost-Ekong, 7 -- Untroubled in the heart of the defence, and looked far more composed than he did - at times - against Croatia.
DF Leon Balogun, 7 -- His partnership with Troost-Ekong in the backline continues to be an area of strength for this team, and the duo appeared boosted by the inclusion of Omeruo.
MF Brian Idowu, 5 -- Sent in a lot of crosses, but it arguably wasn't the best approach as accuracy was low and Iceland's defenders dealt comfortably with the incoming balls.
Replaced at the break after picking up a booking during an underwhelming first half.
MF Wilfred Ndidi, 8 -- Lived up to the billing with an excellent defensive shift at the base of the midfield, as he stifled and stymied Iceland, and cut out the threat of Gylfi Sigurdsson.
MF John Obi Mikel, 7 -- Dropped deeper in this fixture, much to the delight of many Nigerian observers, and excelled when keeping things simple in the midfield. His passing was accurate, although concerns were raised late when he was replaced with what appeared to be a wrist injury.
MF Oghenekaro Etebo, 8 -- Another excellent showing from the midfielder after being afforded a more offensive brief. He still tackled superbly, and was almost unswerving with his passing accuracy.
MF Victor Moses, 8 -- Looked more lively on the ball than he did in Nigeria's opener against Croatia, although he continues to be indecisive.
Worked hard, and contributed the assist for Musa's opener following an exceptional counter attack.
FW Ahmed Musa, 9 -- Nigeria's star man with two goals. Introduced to the side at the expense of Iwobi, but struggled to get involved early on.
His crossing was ineffective, as Iheanacho was squeezed out by the Iceland backline, although he netted Nigeria's opener - and his third World Cup goal - after a fine finish.
He added his second after his pace, composure and agility devastated Iceland's backline having earlier hit the woodwork, fully justifying his inclusion.
FW Kelechi Iheanacho, 7 -- Was outmuscled and outjumped by the Iceland defenders early on, but found some joy by drifting wide and coming deeper. Created three goalscoring opportunities and certainly offered more than Odion Ighalo.
DF Tyronne Ebuehi, 7 -- Defensively adroit at wing-back after replacing Idowu at the break.
FW Odion Ighalo, N/R
MF Alex Iwobi, N/R