Walcott is the youngest player to score a hat-trick for England
Arsenal boss Arsene Wenger has warned England fans not to expect Theo Walcott to repeat his "exceptional" exploits.
Walcott, 19, became the youngest England player to score a hat-trick in the 4-1 win over Croatia in Zagreb.
"What happened you have to consider to be an exception," Wenger said. "Even for players of 25, 26, to score three goals in an international is a one-off.
"But what is very good is that he has the confidence of [Fabio] Capello and he is playing at that level at 19."
And Wenger believes there is more to come from the former Southampton player after Wednesday's stunning display.
"For me, it's important he continues to develop as a team player," he said.
"He's become more of a man, and become more mature in his play. He's developed his link play, his first touch, his commitment and that's normal from 17 to 19.
Arsene Wenger on Walcott's hat-trick
"There's still a lot to come. From 19 to 23, you become a real man - at 19 you're still a boy."
Asked how good he thought Walcott could become, Wenger replied: "Don't set any limitations on any human being. Once you have talent, the rest is down to how much you want it and how intelligent you are.
"I believe he is hungry in a quiet way, with quiet determination. I believe he is intelligent so you can be optimistic."
Wenger said he was heartened by Walcott's measured reaction after the World Cup qualifier.
"That shows he is clever, well-balanced, feet on earth," he said.
"Straight away after the game he analysed the consequences of what happened to him. That is more important for his career than the three goals he scored - that shows a great sign of intelligence and maturity."
Wenger brought the then 16-year-old Walcott to Arsenal from Southampton in January 2006 for an initial fee of £5m, rising to about £12.5m.
He made only 14 league starts in his first two seasons at the Gunners but became England's youngest player, eclipsing Wayne Rooney, when he made his debut as a substitute against Hungary in May 2006 aged just 17 years and 75 days.
He then earned a shock call-up to England's World Cup squad that summer, although he did not make an appearance in the finals.
Now, two years on, the potential that persuaded then England boss Sven-Goran Eriksson to take him to Germany is starting to be realised.
Interview: Theo Walcott
"I am not surprised because he is a player who has got timing with his runs and he is a clinical finisher who can score goals," Wenger added.
"I always believed he will be a fantastic player."
Walcott had to wait until the June 2008 friendly against Trinidad and Tobago before Fabio Capello awarded him his second cap, and then handed him starts against both Andorra and Croatia.
And former England winger John Barnes has cautioned against piling too much pressure on the Gunners forward after his hat-trick.
"He's a great player but let's not get carried away," Barnes told BBC Radio 5 Live.
"The last time we did this, when he got selected for the World Cup, his career halted for 18 months to two years - let's allow him to develop."
Barnes, who won 79 caps for England, suggested the emergence of a number of young contenders, including Walcott, means it is time to draw the curtain on former captain David Beckham's international career.
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