The past 12 months must feel like a whirlwind for Joe Allen. The 22-year-old midfielder has completed a first full season of Premier League football, represented Team GB in the Olympics and signed for Liverpool in a £15m move that makes him the most expensive Welsh footballer in history. Perhaps the biggest reminder of how far Allen has come, though, is that last September he had yet to start a game for Wales.

How times have changed. Allen goes into Friday night's opening World Cup qualifier, against Belgium at the Cardiff City Stadium, not only with his name guaranteed to be on the team-sheet but with the expectation of a nation on his callow shoulders. It is no longer all about Gareth Bale and Aaron Ramsey when it comes to Wales. "There is a difference [from last year], and I think it's quite easy to see that," Allen says. "From my point of view, I'm looking forward to that level of pressure. You aspire to play at the highest levels and be the best player you can, and these are obviously the things that come with it.

"There is a new, added pressure that comes with situations like mine but I've had the experience of being part of the Olympics, which was a help in terms of starting this Premier League season [with Liverpool]. I said to myself that I'm going to approach this year the same as I've approached any other in my football career and give it everything I can, and at the end of the day say to myself: 'Have you given your best?' If you have, you can't do any more than that."

Few Liverpool supporters would have any complaints with Allen's contribution since he joined the club. Although the team have struggled and made the worst start to a season in 50 years, it says much for Allen that he has still managed to catch the eye. It felt like a lot of money when Liverpool activated the £15m release clause in Allen's contract, but it is already looking like a sound investment. "Flattering" is how Allen describes Liverpool's pursuit of him. "The level of faith that has been shown in me can only inspire me to go out and perform on the football pitch," he says.

Allen is softly spoken and looks younger than his age, although when he talks he does so with great maturity, sounding more like a seasoned professional than someone who has yet to start 100 league games. That confidence shines also through on the pitch, when a player who stands only 5ft 6in tall seeks to dominate the midfield with his incisive short passing. "You have to have massive belief; it has to borderline on arrogance at times," he says. "I think you can see the difference of a top player playing with belief or without it. That's something you have to cope with in football and something we strive to achieve."

Allen hardly needed his arm twisting to move to Liverpool, although that never stopped Craig Bellamy, his Wales team-mate, from urging him to follow in his footsteps. "He couldn't speak more highly about the football club. It's a club he loved being a part of – he had two spells there and you could see how much he enjoyed his time there," Allen says. "He said that all the ingredients are there for you to develop, kick on and be the best player you can. It was good to hear that from a player who has been at top clubs and played at the highest level."

At times there is a sense that Allen is still trying to make sense of everything that has happened to him in the past year. He was only eight years old when Steven Gerrard made his debut for Liverpool and Allen spent the next decade idolising the captain he now shares a dressing room with. "He's been an inspirational figure throughout my childhood and it's a privilege to play alongside him," Allen says. "There is no end to the things that I'll be able to learn from him."

Wales hope that they will see some of the benefits, starting with the game against Belgium, which feels like it has got tougher since the draw was made. Belgium, after failing to qualify for a major tournament since the 2002 World Cup, are ready to come back with a vengeance. They have assembled one of the strongest squads in Europe and include a number of Premier League stars in their ranks, including Marouane Fellaini, Eden Hazard, Vincent Kompany, Thomas Vermaelen, Jan Vertonghen and Moussa Dembélé.

"I think it's natural sometimes to focus on the opposition, the players they've got and the stars they've got in their team. But I think it's important sometimes to remember the talent and ability that we've got in our team," Allen says. "Having said that, I think it's been well documented, especially over the summer, the players they've got and the transfer fees they've commanded. We'll all have to make sure that we're on our toes because it's going to be a very tough encounter.

"Last season two of the toughest opponents I came up against were Fellaini and Dembélé. I think Fellaini is a bit of man-mountain – he's a beast. There's not many people who could get into a physical battle with him and come out on top. Whereas Dembélé is probably slightly more mobile with the ball – he carries it really well. I think we saw that with the Fulham game at Manchester United game recently.

"They've got such an array of talent that it's going to be tough to fit them all into one team. Hopefully that will be a problem for them in some ways. I think we can talk so much about their team and work so much on them but at the end of the day, we need to focus on how well we can perform. It's a fresh start for us to make our mark in the group and we're looking forward to getting things going with a positive result on Friday."