Arsene Wenger insists the "moment has come" for his Arsenal side as they prepare to face Barclays Premier League leaders Chelsea at the Emirates Stadium on Sunday.

The Gunners - who have a match in hand on their title rivals - will be looking to close an eight-point gap on the Blues after slipping further off the pace in the wake of last weekend's lacklustre defeat at Sunderland.

Confidence within Wenger's squad, however, remains high after they returned to winning ways with a 2-0 win over Standard Liege in midweek to book a safe passage through to the knockout stages of the Champions League.

"Everyone will look at the game to rate our potential, and I have no worries about that," said the Arsenal boss.

"We are ready for the game, are well focused, prepared and the confidence is good.

"We just want to focus on the game like we want to play it."

Wenger declared: "It is a big test, yes - but that is what you want, to play these teams.

"I think there is a period for any team to come out and show its strengths. For my team, this moment has come.

"We are not any more a team that has to be considered to be young.

"I think we have the strengths and we can show that on Sunday that we are strong enough to compete."

Arsenal, though, must take on the Premier League leaders still missing striker Robin van Persie and full-back Kieran Gibbs, while centre-back William Gallas is rated as only 50/50 to face his former club.

Even with Arsenal's defensive reshuffle, Wenger knows full well whoever is in the backline on Sunday will face a stern examination from Didier Drogba and former Gunner Nicolas Anelka.

"You know they are a good side and to beat them, you have to deliver a good performance," said the Arsenal boss.

"It is more important we focus on what we do than any strength or weakness of Chelsea.

"They are a strong side and have a good manager in Carlo Ancelotti, but I still believe that despite all that, we can still beat them.

"Let us expect them to be strong on the day, and then let us be stronger."

With Denmark striker Nicklas Bendtner still a couple of weeks away from recovery after groin surgery, Wenger is short of options for the central role in Arsenal's fluid three-man attack.

Both Croatia's Eduardo and Mexican teenager Carlos Vela have been deployed there without great impact in recent matches, so England forward Theo Walcott could well be given an opportunity.

Wenger revealed there was "a chance", albeit perhaps slim, the former Southampton trainee will start at the head of the frontline on Sunday.

However, it is a role which the Arsenal manager feels Walcott - with high hopes of making Fabio Capello's squad for South Africa - will grow into naturally.

"The only thing I would say with Theo is that every time I have rushed him back he has got injured again. This time I have decided to take the time to get him completely 100 per cent fit to come back," said Wenger, clearly irked by the 20-year-old's lack of availability this season after a busy summer with England Under-21s and an early campaign blighted by fitness problems.

"Theo can play central, I am very conscious of that because of the quality of his runs and the timing of his runs, the other part he can work on."

Wenger maintained: "I believe he has all the assets to be a fantastic central player.

"What he needs to work on to play in this kind of position is the back to goal.

"At the moment his strengths are central to the counter-attacking role rather than the distribution role. That is what he has to add to his game."

Arsenal, meanwhile, are dedicating the Chelsea match to the Great Ormond Street Hospital Children's Charity.

Players and some staff will donate a day's wages as the club aim to hit their £500,000 target for the season.

Wenger said: "With football, we are in our own passion. Sometimes you are tempted to be selfish and forget a bit about the rest of the world.

"Charity brings us down to earth and back to real life."