Eidur Gudjohnsen, once Iceland's history boy, was in danger of becoming their forgotten man two years ago. A player who had twice won the Premier League with Chelsea and, even more impressively, the treble with Barcelona in 2009 had drifted into an irrelevance at the top level. Rejected by Fulham, Stoke City and Tottenham, Gudjohnsen went to play for AEK Athens in 2011, the Greek club persuading him to join them with the promise of regular football and a fresh challenge in a new country. It seemed like a good opportunity. Yet in October, in only his 10th game for the club, he suffered a double leg break against Olympiakos, a potentially ruinous injury for a player who was 33, and then agreed to terminate his contract at the end of the season.

Where once Gudjohnsen made history by coming on as a substitute for his father, Arnor, when he made his international debut against Estonia in 1996, now he was on the verge of being consigned to it. By his own admission, the forward was "a bit of a journeyman". He had a trial with Seattle Sounders but it did not work out; instead he ended up in Belgium last September, signing for Cercle Brugge, where his form improved enough to earn a move to Club Brugge in January of this year and, then, a return to Lars Lagerback's Iceland squad. They were pushing hard to qualify for the World Cup for the first time and with the experience of Gudjohnsen, the best player in their history, were able to finish second behind Switzerland in their group, qualifying for the play-offs. On Friday night they host Croatia in the first leg in Reykjavic and the country is approaching fever pitch. Even Gudjohnsen, so cool and collected, reckons that victory would be as good as any trophy he has won, and he has won some important trophies.

Iceland, Gudjohnsen says, have always had good players but never at the same time, entirely understandable bearing in mind their population of 300,000. If they do beat Croatia, they will be the smallest country, population-wise, ever to compete at the finals and to put it even further into context, Iceland were among the lowest seeds in Pot Six when the qualifying draw was made in June 2011. The Faroe Islands were in Pot Five. Yet, though the wider world did not know it, there was optimism in Iceland, especially when they were given a slightly favourable group. A new generation was emerging and the current side largely comprise players who featured in the European Under-21 Championship two years ago.

"It feels great," Gudjohnsen says. "I think obviously we are aware of the enthusiasm of all the people at home. It's like people are counting down to Christmas. It's an amazing atmosphere. It's something completely new for everyone. We've already achieved something that's never been achieved before for the Icelandic national team and we're the first team to have ever gone into the play-offs as the sixth seeds in the group. It's already been an amazing achievement but it could be so much better.

"I had my first game in 1996 and it's an atmosphere now that I've never seen in my time with the national team. I've never known people so excited. We've always had good spells or had a result which raised a few eyebrows or we came up with a surprise here or there but we've never actually managed to raise the expectations of the people so much, as we have done now, because not only did we have some good results, we did it time and time again. Games that we were expected to win, we did and it's taken us where we are now.

"A generation of players that have come through now who are very good. When they were at Under-21 level, they went all the way to the European Championships. We've got a group of players playing at a higher level at the same time while in the past we've always had some good players but never in the same generation."

It is an incredible story – and perhaps a final chapter will be included in Brazil next summer – and Iceland have done it on the quiet. Few people tipped them to be the next big thing.

"It's a little bit out of the blue but I've got my theory on it," Gudjohnsen says. "It's probably about 13 years ago when we had our first full-sized artificial pitches built inside. If you look at most of the boys I'm playing with now, they must have been 10 years old, so they're probably the first generation able to play all year round in Iceland. They're coming through now and we're reaping the benefits.

"Since then we've got approximately another 10 across the country. Football used to be played five months a year here – six months maximum. And then it just used to be pre-season or indoor football on wooden floors. It wasn't the same. This is the first generation able to play all year round growing up. They moved abroad, all of them, at a fairly young age to develop their own careers."

Croatia will provide a stern test, even though they have replaced their coach, Igor Stimac, with Niko Kovac after they failed to win their group. They have not won in their past four competitive matches.

"It's been the story of our group stage as well," Gudjohnsen says. "It's the fourth team that we play against that have switched managers so in that respect we are going into the unknown a little bit – how they are going to play. Going into the play-offs, we always knew we were going to draw a strong country. Croatia have got a lot of excellent players. We just have to make sure we play to our best over the two games.

"Small details can make a big difference in these games. With a bit of luck, if things go with us, we might surprise a few people again. One thing's for sure, it's put Iceland on the map. Everyone seems to be taking notice of Iceland in recent times. It's much bigger and better. For me, it would be the perfect way to say goodbye. Croatia have great individuals. It will just be the form on the day."

Gudjohnsen never benefited from the facilities available to today's youth, although he was lucky enough to spend much of his childhood abroad because of his father's career. "Maybe I'm one of those who just, without blowing my own horn, was an exceptional talent," he suggests.

He was, though he is a little slower in his position behind the striker now, and he laughs at the suggestion he is the father of the team at the age of 35. "I am the oldest apart from our second goalkeeper who's older than me," Gudjohnsen says. "I'm the oldest outfield player. It's all a little bit slower than what it used to be. I just try to use my experience. That's what you do when you come to the end of your career.

"You might not make as many runs as you used to but you make clever runs and keep the ball when it's needed for the team. You keep everyone calm when it's needed. It's been going well. Pace is in the mind many times. You've got physical pace but pace in thinking, in reading the game. That's always been one of my stronger points anyway."

Lagerback has said that Gudjohnsen has a "good football eye", which is partly what has allowed him to recover from his lowest ebb. Gudjohnsen says he misses English football – "even the press" – but after leaving Barcelona, he struggled, suspicions growing about his hunger and drive.

Gudjohnsen helped Tottenham qualify for the Champions League during a brief loan in 2010 but subsequent spells at Stoke and Fulham were unsuccessful. He thought that Fulham might sign him permanently at the end of the 2010-11 season, only for Mark Hughes to quit. He drifted off the scene, broke his leg in Greece and playing for Iceland again started to become a distant dream.

"It's difficult to say when you're 33 and you have a double leg break," Gudjohnsen says. "You have your doubts if you'll ever come back. I had to show a lot of patience and desire to come back. The national team was one of the things that gave me some inspiration. I saw these boys doing well and I wanted to get back in and I didn't want to end my career with an injury. I wanted to get back into playing regularly. It gave me good inspiration in some difficult times. It's great to be part of it.

"But I have no regrets, I've just enjoyed the experience. Everything you do in life is an experience and probably everything I've been through in the past few years has given me the extra desire to finish my career on a positive note."

Gudjohnsen respects Lagerback, the 65-year-old Swede who led Sweden to five consecutive major tournaments and Nigeria to the World Cup in 2010. "He's got a calmness about it," he says. "People respect him a lot, both for what he does and as a man. He's very gentle in the way he speaks and he seems to get the best out of the players. The players are willing to go as far as they can for him."

Lagerback is a little different to the managers Gudjohnsen has worked with before and he chuckles when it is mentioned that José Mourinho, who he played for during the Portuguese's first spell at Chelsea, allegedly sparked a mass brawl in the tunnel following the 2-2 draw with West Bromwich Albion last Saturday after he called Jonas Olsson a "Mickey Mouse player".

"I love José," Gudjohnsen says. "I won't be backing things like that but I had a great time under José. He's a character. We all love him in the sense that everyone who follows football knows that we are going to get some excitement from him in one way or another. Plus he's got an unbelievable winning mentality. I think he's amusing whether you like him or not." Gudjohnsen still watches Chelsea but believes the side has not quite clicked yet. "But they will be there or thereabouts at the end of the season," he says.

A team managed by Eidur Gudjohnsen would have "strong English defending and Spanish flair up front", although he is not quite sold on the idea of becoming a manager yet. He is coming round to it, though.

"Up until now, I've always said I won't go into management," he says. "But then as you get closer to the end, you feel like you've got a lot to give. A lot of advice to give and a lot of ideas of how you would want your team to play. I've obviously worked with a lot of top managers. You never know.

I'm leaning towards it more than I have done in the past but that is not to say I will definitely go that way. I thought about starting my coaching badges. I might start in the new year. But I really haven't decided. I'm just enjoying my football too much."

For now, Gudjohnsen's only focus is beating Croatia, and going to Brazil.