VOLGOGRAD, Russia — The last time Iceland pulled off a huge surprise at a major tournament, it was stung by a big letdown.

That's something the team will be wary about when it faces Nigeria at the World Cup on Friday, six days after holding Lionel Messi and his Argentina teammates to a 1-1 draw in the opening Group D match.

"Whenever everyone is rowing in the same direction, anything is possible in football and we have to stick together," Iceland captain Aron Gunnarsson said. "We know it's another tough task for us tomorrow."

Iceland has every right to be on a high following the draw against Argentina. The Nordic island country, the smallest nation in the tournament's history, is playing in its first World Cup. Argentina, by contrast, is one of the sport's powerhouses, the winner of two World Cups and runner-up four years ago in Brazil.

The adrenaline rush after Saturday's match in Moscow, which took place at 4 p.m. local time, lasted so long that Gunnarsson said he couldn't get to sleep until 4 a.m.

That draw, in which Messi missed a penalty kick, was as big as the team's 2-1 victory over England in the round of 16 at the 2016 European Championship in France. That result, though, was followed by a 5-2 loss to the host team in the quarterfinals.

Were it not for the spirit of the team, particularly in the second half, the result could have been a lot worse.

So against Nigeria, the Iceland team knows it has to keep its emotions in check to get anything out of Friday's match in the southern Russian city of Volgograd. If Iceland wins, its prospects of making the second stage would be in its own hands regardless of what happens Thursday between Argentina and Croatia. If Nigeria loses it will be eliminated.

Gunnarsson said he and his teammates have fully recovered to take on the more physical challenge of facing Nigeria. However, Iceland could be without winger Johann Berg Gudmundsson, who was substituted during the match against Argentina with a calf injury.

Iceland coach Heimir Hallgrimsson said he was "not going to hide" the fact that Berg Gudmundsson is unlikely to recover in time, and added that there will be changes in the lineup.

Hallgrimsson said it was always his intention to alter the team because of the different threat posed by Nigeria.

"We," Hallgrimsson said, "expect to win."

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