Arsenal must be "alive and alert" and get their heads right after the disappointment of Tuesday's Champions League defeat, according to Theo Walcott.

Goals from Toni Kroos, Thomas Muller and Mario Mandzukic secured Bayern Munich a 3-1 win in the first leg of their last-16 tie at Emirates Stadium - with only Lukas Podolski's second-half header offering comfort to Arsène Wenger's side.

Walcott admits he has not faced many better teams than the Bundesliga leaders but he doesn't think Arsenal are miles behind Bayern. They just haven’t yet found a way to maximise their potential.

"We’ve got some great talent in that dressing room, it’s just all about putting that into one bowl," said Walcott.

"We’ve had a lot of slow starts, and just give ourselves a lot to do. It’s always difficult because you’re chasing the game then. You leave gaps as well, because you take chances that you wouldn’t really [if you weren’t behind].

"Bayern are at the top of their game with fantastic, young players. They’re experienced and have won a lot. They’re one of the best teams I’ve faced, without a doubt. Throughout the whole 11 on that pitch on Tuesday, I felt they were very well organised.

"But I think we’ve got the best man for the job to get our heads back where they should be. I’ve played a lot of games in the Champions League and I know how things go. We need to react in a positive way straight away.

I think we’ve got the best man for the job to get our heads back where they should be

Theo Walcott

"We can’t be down in the dumps in training. Everyone needs to be alive and alert. We’ve got a good run in the Premier League and we can’t forget that. We’ve just got to start believing how good we are again."

Much has been made of Arsenal's eight-year wait for a trophy but Walcott just wants to concentrate on Saturday's huge game against Aston Villa.

"If you’re a top team, the saga of not winning something for such a long time is always disappointing," he said. "I don’t want to focus on the negativity about that. I want to focus on getting the positives out of the team because I know how good these guys are.

"[We have to] get back to where we should be and start by beating Villa. We need to be a bit more dominant when teams come to the Emirates. That hasn’t happened of late. We’ll get there. I’ll show my belief to all the guys and I’m sure they’ll do the same."

Copyright 2014 The Arsenal Football Club plc. Permission to use quotations from this article is granted subject to appropriate credit being given to www.arsenal.com as the source Chris Harris 20 Feb 2013