Norwich's Swedish stars Martin Olsson and Johan Elmander have been urged to hold their nerve to clinch a World Cup trip to Brazil next summer.

The Canaries' duo will have a prominent role in Stockholm tonight as the Swedes bid to overturn a 1-0 first leg deficit against Cristiano Ronaldo's Portugal.

The Real Madrid superstar's late header separated the sides in Lisbon last week, but Swedish coach Erik Hamren believes Zlatan Ibrahimovic and Elmander can still fire his country to the finals in 2014.

'There were too many long balls to Johan and Zlatan on Friday and we didn't have the energy to support the attack. We've got to have more quality when we win the ball,' said Hamren. 'We need to score, that's for sure. It's not Ronaldo versus Zlatan, it's Portugal versus Sweden. They can play more for the result, they have an advantage in that. We meet a really good team with really good international players so we can't start the match and just go forward and have the ambition to score easy and early because then they're going to punish us quickly.'

Hamren is under no illusions what could happen if he fails to guide his country to the finals with the Swedish boss confirming some of his players have been practising penalties in the event the tie is decided by a sudden death shoot-out.

'It's happened to me a few times before as a club coach, when you know that if we lose a game there's not much left of the job,' he said. 'I'm not thinking about that one bit. My focus is on succeeding and if we do succeed we don't need to discuss it.

'Those who are used to taking penalties, they don't need to have some training because they do it a lot, but the players who aren't used to taking penalties, they took some (at training). It's a mental thing of course and if it's been a long time then they need to have done it before the game.'