Iceland are sweating on the fitness of Gylfi Sigurdsson and Jóhann Bergs Guðmundsson, ahead of Friday’s Group D clash against Nigeria.

Everton star, Sigurdsson, who missed the latter part of the English Premier League season last term due to a knee injury, did not train with his teammates on Tuesday morning.

Instead, he was involved in a light exercise with physical trainer, Friðrik Ellert Jónsson.

Guðmundsson, who plays for English club, Burnley sustained a calf injury in the 1-1 draw against Argentina in the first fixture and remains doubtful for the encounter.

The game will be played at the Volgograd Arena at 4pm Nigerian time.