Walcott was a shock inclusion in Sven Goran-Eriksson’s 2006 squad for the Germany tournament, having never kicked a ball in the Premier League at the tender age of 17.
Four years on, Walcott admits he never should have been to the tournament, but insists he is there on merit this time.
“It's nice to get the chance to play and to deserve to play. I didn't deserve to play or to be in the squad at all in 2006," he said.
"I'd not played in the Premier League and it's just not heard of."
The 21-year-old started Monday evening’s friendly with Mexico, playing the majority of the game on the right wing - his adopted position in an England shirt.
With Aaron Lennon also pushing hard for the same position, Walcott could once again find himself a mere passenger in South Africa this year should he make Capello’s final squad.
"Hopefully I can play again [against Japan on Sunday] and have a good game," Walcott said. "I'm just trying to play well and train well and hopefully I'll be in the 23.
"I don't think anyone's place is guaranteed yet so we'll be working hard like we did last week in training in Austria."
Walcott’s England career has been plagued with inconsistencies and frustration to date.
A blistering performance at the beginning of the Capello reign saw the Arsenal forward bag a magnificent hat-trick against Croatia in Zagreb, but since then his form has been patchy for both club and country.
His place in the side has come under regular scrutiny following a lack of first team action at Arsenal this season, as well as his indifferent performances in an England shirt.
But the winger remains a favourite of Capello’s for his potential to produce, and is likely to make the final squad which is to be announced on June 1.
By Joe Brewin
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