Walcott was a substitute on Saturday in Arsenal's first competitive match at their new Emirates Stadium in front of 60,023 fans.

The Gunners were losing 1-0 to Aston Villa when the 17-year-old came on in the 73rd minute -- and he set up Gilberto's equaliser 11 minutes later.

"There were no nerves, not at all, although I did go to the toilet just before I came on so there might have been a bit there," Walcott said, according to London's Evening Standard newspaper on Monday.

"But once I had the first touch of the ball, the confidence came to me.

"I was so up for it. I have been waiting a long time, but I have been so patient and I have to thank the boss for playing me. He just told me to go and do the stuff that got me in the squad. I will play anywhere -- left, right or up front. As long as I'm on the pitch, I'm happy."

Walcott was included in Sven-Goran Eriksson's World Cup squad and made his England debut as a substitute in their warm-up match against Hungary in May.

Eriksson had only seen him in training and Walcott had played just 23 times for his former club Southampton in The Championship, England's second tier, with his last competitive match being in January.

"It was a brilliant experience for me training with world-class players but I just want to concentrate on Arsenal now," Walcott said.

"Dealing with the pressure and watching how players prepared for big games helped, but now it's gone I just want to think about Arsenal. I didn't feel pressure -- you shouldn't at 17 -- but I was picked and it didn't affect me."

England's new vice-captain Steven Gerrard criticised the decision to take Walcott to the World cup in his forthcoming book, saying the youngster had "no right" to be in the squad.

But Arsenal manager Arsene Wenger leapt to Walcott's defence.

"I think the criticism he has been given has been harsh. It is a lot of pressure for a very young man to deal with.

"I can accept players being criticised if they play badly -- but to criticise them when they do not even play is harsh. He is very young, but people want him to be a star in England."

Wenger believes Walcott could have done a good job had Eriksson given him a taste of competitive international action.

"I never said he should definitely go to the World Cup -- I just said that I would be happy if he did go," the Gunners boss insisted.

"Was he ready? He is playing against Aston Villa -- and that is no harder than playing against Costa Rica or Ecuador or a side like that.

"Sven decided to take him and then he did not decide to play him -- that is an issue for him and not for me.

"Theo should not be criticised for that. He will also get much better -- he is a very good listener. He was a little bit happy for having been there -- but also frustrated for not having played.

"He is, though, the sort of player who will always bring something to the team when he plays and I have always felt that."

Arsenal take on Croatian side Dinamo Zagreb at the Emirates Stadium in the second leg of their Champions League qualifier on Wednesday.

The Gunners lead 3-0 from the first leg.