By Chris Harris

Theo Walcott's back injury is a direct consequence of his international commitments with England this summer.

That's the opinion of Arsène Wenger, who admitted on Friday that we are unlikely to see Walcott back in an Arsenal shirt until next month.

That means the 20-year-old will definitely miss next week's Champions League tie with Celtic and the big Premier League clash at Manchester United next Saturday.

Walcott played in England's friendlies against Kazakhstan and Andorra in June and was then called up to the Under-21 squad for their European Championship campaign in Finland. As a result Walcott only managed 45 minutes for Arsenal in pre-season - against Valencia on August 8 - and he sustained his back injury during that game.

Wenger was always against Walcott's dual international role and he believes that the player and his club are now paying the price for those summer exertions.

"Theo will not be available for the Man United game. I believe it will be a problem for England as well," said Wenger at his pre-match press conference.

"He has an inflammation of his lower back. At the moment straight line running is OK but no curves.

"That's why last year I didn't want him to play for the Under-21s. I know how it works. The player comes back later than everybody else, he doesn't have a decent preparation, you are under pressure to rush him back, you play him earlier than you should, he gets an injury, and you see him again in October.

"That's what usually happens and that's why I was adamant that he does not go with the Under-21s. He had no decent preparation for the championship, for the season, and in the end England will pay the price as well."

Walcott found himself in an unusual position because he exploded onto the international scene with a hat-trick in Croatia last September while he was playing a key role in the Under-21s' qualification campaign.

Wenger understands the predicament but he believes that, once a player breaks into the senior squad, he should leave the Under-21s behind.

"Once a player is already playing for the top national team, what is the reason to take him with the Under-21s, who are originally destined to promote the players to the first team?" asked the Frenchman.

"That's what I couldn't understand.

"It is not anger [I feel] because I knew at the start what could happen. But it is frustration, yes, because I can't see the logic in that whole process. In the end, England, and Arsenal, have a handicap."

Copyright 2014 The Arsenal Football Club plc. Permission to use quotations from this article is granted subject to appropriate credit being given to www.arsenal.com as the source 21 Aug 2009