Nigeria made a perfect start at the Under-20 World Cup on Sunday, thrashing Guatemala 5-0 in their Group D opener in the Colombian city Armenia.
Two Edafe Egbedi first-half goals and second-half strikes by Abdul Ajagun, Olarenwaju Kayode and Ahmed Musa were enough to sink the Central Americans.
The Flying Eagles now top the group on goal difference, after Saudi Arabia beat Croatia 2-0 on Sunday.
Coach John Obuh's side next face Croatia on Wednesday.
"It was a good game but my players played a little below expectations as there were a few tactical things they didn't observe," Obuh told BBC Sport.
"But I am sure they will play better in the second game."
"Nobody should write off Croatia because I have looked at their team and they might present themselves better against us than they did against Saudi Arabia."
Against Guatemala, it only took two minutes for the Nigerians' power to be felt as Ramon Azeez fired a powerful shot over the crossbar.
Six minutes later, Musa edged past Jose Andrade down the left flank and slotted back to Egbedi, who fired home from close range.
Egbedi doubled Nigeria's lead in the 39th minute, guiding home a fine cross from Musa.
And though Guatemala had a better showing in the second half, the Nigerians maintained their dominance.
Abdul Ajagun hammered in a Kayode cross at the start of the second half before Kayode scored the fourth in the 52 minute as he dodged the Guatamalan defence to nod in an Emmanuel Anyanwu cross.
Playmaker Musa then sealed the fate of the Guatamalans with a powerful strike in the 76th minute.
This is Nigeria's eighth appearance in the tournament, but the west Africans are yet to win their first title despite having reached the final twice.
On Saturday, other African representatives Cameroon drew 1-1 against New Zealand in Group B, with Mali losing 2-0 to South Korea in Group A.
Egypt, who started on a good note when holding two-time champions Brazil to a 1-1 draw, play Panama later on Monday, while Brazil faces Austria in the other group match.