LONDON, ENGLAND - ARSENE Wenger admits Arsenal's lack of experience has made it harder than ever for his side to win the Champions League.

The Gunners face Porto in their second Group G match on Tuesday and Wenger knows a victory at the Emirates Stadium is essential because he can no longer guarantee success away from north London.

Wenger believes his young side are less likely to thrive in hostile territory because they are still learning how to control the tempo of matches.

Wenger's decision to pack his squad with promising prodigies rather than proven, world-class stars means Arsenal's long-term future is brighter than almost any club in Europe.

But the present is shrouded in rather more doubt while those youngsters go through their growing pains - as Saturday's shock 2-1 defeat against Hull proved all too clearly.

'The side we played against Dynamo Kiev was very young. Theo Walcott is 19, Alexandre Song is 21, Denilson is 20 and even Cesc Fabregas is only 21,' Wenger said.

'It is not easy to win away in the Champions League with such a lack of experience.'

That defeat against Hull was only Arsenal's second loss in 60 matches at the Emirates and another against Portuguese champions Porto would leave Wenger's side in danger of missing out on the knock-out stages.

With trips to Fenerbahce and Porto still to come, Wenger believes this is the toughest group he has faced in 12 years with Arsenal.

'This group is tougher than in previous years. It is definitely the most even group we have had because there are no easy games,' he said.

'That makes the match with Porto more important. We know in the Champions League you qualify with 10 points, so if we win our home games we are through.

'If we can do well, then the other teams will take all the points off each other and that is why I think even draws from our away games could prove good results because all the teams will drop points.

'There is no obvious weakest team, so every game will be very important and we will have to be at a high level for every game.'

Even if Arsenal can't win the Champions League, Wenger has no doubts that England's clubs will continue their recent dominance of the competition.

'From what I've seen so far I would say the four English teams are the favourites. Inter Milan, Barcelona, Lyon and Bayern Munich are all behind them,' Wenger said.

'Teams from abroad now know that if you get an English side you have a really tough job.

'But that means the fans' expectations are higher. They expect us to beat every team we play because of how well we have done before.'

Wenger's admission of Arsenal's fragility increases the concern that his squad are capable of producing great moments rather than winning major prizes.

But, while Cesc Fabregas is at the heart of the team, they will always have a chance of beating the best.

The Spanish midfielder's elegant play sometimes disguises his fiercely competitive nature and he is determined to make amends for a disappointing display in Kiev.

'We were not happy with the result in Kiev, because we had the chances to win, myself included,' he said.

'We are not used to missing such chances, and then they scored the penalty.

'It was the last seconds of the game before we could get back and we did not have time to make the winner.

'We were disappointed with that, but we all hope we can have good reaction against Porto.' -- AFP