From the moment he sits down, pouring himself a glass of water and surveying his audience, Theo Walcott radiates confidence. One of his more fearsome inquisitors tells him that “now we're going to see whether all that media training has worked”, at which the 19-year-old laughs, denies having had any such training and proceeds to give a performance that not only disarms but endears.

Assignments such as this, though, have never been the problem for Walcott, who seemed at ease with the media from the moment he was thrust into the spotlight as a 17-year-old by Sven-Göran Eriksson's baffling decision, when in charge of England, to take him to the 2006 World Cup finals in Germany. The player admitted yesterday to having been “star-struck” that summer, an impression he had conveyed by walking around the England team hotel in Baden-Baden with a camcorder, and that in the past two years he has not progressed as quickly as he may have expected. But now he is beginning to feel at home in such elevated company.

Walcott knew that he had arrived as an international player late on Saturday afternoon when Fabio Capello, the England manager, read out the team to face Andorra and he was in, ahead of David Beckham, on the right wing. Beckham told him to “go out and enjoy it” - and enjoy it Walcott did, at least for the first 20 minutes, as he, alone among the England team, showed the opposition to be the amateurs they are.

Praise of his performance should come with the caveat that his threat faded once he was subjected to some crude challenges, but it was promising enough to have given him hope of retaining his place in the starting line-up against Croatia at the Maksimir Stadium in Zagreb tomorrow evening, a night on which Beckham has suggested that experience is called for.

“I suppose I haven't started that kind of game before,” Walcott, who was often deployed as a substitute in Arsenal's Champions League away matches last season, said. “But I play with no fear, so it's not going to bother me. I will treat it like any other game. That's all I can do.”

This was a recurring theme, as if he wanted to say that his youthful innocence makes him immune to the “fear of failure” of which John Terry, the captain, spoke on Friday. But maybe the fear factor that Capello will be weighing up is the one that Walcott could inflict on the Croatia defence. If pace is the one thing that frightens defenders, Walcott is perhaps the one player in this squad who has the ability to scare opponents. Capello appears to have a distrust of raw speed, having shown little inclination to select Micah Richards, Gabriel Agbonlahor, Ashley Young or, most notably, Michael Owen, but he has seen something that he likes in Walcott.

So has Arsène Wenger, the Arsenal manager, who, having previously used Walcott mostly as an impact substitute, has started him in four of the club's five matches this season. “The main thing he [Wenger] has told me this season is to be more aggressive, win the ball back and get at defenders and not to have any fear,” Walcott said. “That's the main thing I've taken to my game this year. I'm still learning the position, but my link-up play has improved and so has my touch.

“I think I can give the team a different aspect by getting behind defenders. There are some world-class players who can play right wing, but I give them a different option. Sometimes people are negative about my final ball, but I think it's not too bad. I've had quite a few assists and I'm learning. It's like with Cristiano Ronaldo; he came to Manchester United in his first year, showed some brilliant tricks and now he's 23 and he's the best player in the world. I'm not saying I will be like Ronaldo. I will be myself.”

Ronaldo succeeded Beckham in the Manchester United No7 shirt, proving to be superior to the man he replaced. Walcott wore the same number for England on Saturday and hopes to retain it in Croatia. Others have tried and failed to replace Beckham in recent years - Shaun Wright-Phillips, Aaron Lennon, David Bentley - but when the team trained at the Olympic Stadium in Barcelona yesterday lunchtime, their final session before flying to Zagreb this morning, it was Walcott who figured most prominently, with the former captain on the periphery. It may prove to be a night for experience in Zagreb, as Beckham has suggested, but there must be a part of Capello that is intrigued to discover whether Walcott is as fearless as he claims.