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Crystal Palace striker Jorgen Strand Larsen is one of those dealing with health issues, Solbakken added.

"We've really only had Jorgen who has had a fever, but then there's been a bit of coughing and rasping scattered throughout," Solbakken said.

"But there's air conditioning, flights, changing rooms and all that.

"There's 50 people [in Norway's travelling party], so it would be strange if something or other didn't crop up."

Marcus Holmgren Pedersen missed the 2-1 win over Brazil in the Round of 16 because of illness, although Solbakken thought the pressure of the FIFA World Cup experience may also have affected the 25-year-old.

"I think, without being a doctor, that it's a combination of the boy being young, he's come to the [FIFA] World Cup and thought, 'I'm going to be a back-up for Julian [Ryerson]', he's had two games and played great," Solbakken explained.

"He's got a lot of stimulation, his head is full, his body is full of impressions, and then the system collapses a bit."