The 17-year-old made his long-awaited debut as a 73rd-minute substitute against Aston Villa on Saturday. He made an immediate impact and even played a part in Arsenal's equaliser four minutes from time.
"It was a big experience to come on with all these world class players and 60,000 people here," Walcott said afterwards. "It was a really big thing for me. I didn't even expect to be in the squad but I was so up for it.
"I know I have worked hard to get there. I have been waiting a long time. I have been so patient and I have to thank the boss for playing me.
"Once I had the first touch of the ball, the confidence just came into me."
Walcott's selection for the England World Cup squad means he has enjoyed many more newspaper column inches than Premiership minutes. That equation will start to change from now on.
"The World Cup was a brilliant experience for me," he said. "Dealing with the pressure and watching how players prepared for big games has helped, but now it's gone I just want to think about Arsenal.
"[Against Villa] the boss just told me to go and do the stuff that got me in the squad. I'd like to play centre forward, but I don't mind where I play - left, right or up front - as long as I'm on the pitch I am happy.
"[On Saturday] I just wanted to come off the bench and do
well. Now I want to get a start. I'll just work hard in
training and see where it takes me."
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