KHUTOR, Russia (REUTERS) - Norway's male cross country skiers sounded both mystified and downhearted on Sunday after a Winter Games where they started as one of the favourites but underperformed badly.

In the six events they contested, they won just one gold and a bronze.

Sunday's 50km freestyle mass start was the last chance to claim a podium finish but once again Norway left the course without medals. The best performer was Martin Johnsrud Sundby, who ended in fourth.

"Of course we dreamed of winning a medal today. But everyone knows that our team just is not strong enough at the moment," he told reporters.

"We need to find more motivation. This is something that is clearly lacking at the moment. We plan to train even harder and finish the season on a high." Particularly disappointing was the performance of double Olympian gold medalist Petter Northug, who won the 50km classic race in 2010 and also took a gold in the team sprint.

The 28-year-old ended up in 18th on Sunday and failed to win a single medal in Sochi. He told reporters that an injury had caused him to miss three and a half months' training.

"I understand that I am in poor form. It is particularly sad that our men's team as a whole did not perform well here," he said.

"It has been a long time since we have experienced such poor results. It is very, very disappointing." Northug's comments were echoed by Russia's Alexander Legkov, who won Sunday's race.

"It is clear he was not in the best of form ... but I want to say the following - finally I became as good as him," said the 30-year-old Russian.

The men's lack of success contrasts with the Norwegian women, who won four golds, two silvers and three bronzes.

Chris Andre Jespersen, who finished 32nd, said the 50km race had been tough and chalked it down to a bad day, noting the team had had ski problems in two earlier contests.

"Of course we should have won more medals at these Olympics. Why couldn't we do this? Well, in the classical style race and in the relay we had problems with our skis. But today we have no excuse," he said.