The 32-year-old Portsmouth defender has not featured for England since last summer's World Cup.

However, an impressive debut campaign with Pompey last season raised hopes of a first call-up under the new coach.

McClaren resisted calls for such a move last term but, with injuries to skipper John Terry, Tottenham's Ledley King and Middlesbrough's Jonathan Woodgate affecting his planning for the August 22 friendly with Germany, he feels the time may now be right to use Campbell's experience once again.

McClaren has always said he would never slam the door on anyone's international career, although such talk was generally greeted with scepticism.

Yet McClaren backed up his words with actions by bravely restoring David Beckham to the England fold for the June friendly with Brazil and crucial Euro 2008 qualifying win in Estonia.

Having seen that move pay off handsomely, McClaren feels Campbell can have a similar effect on the England side facing up to five key qualifying games that will determine their Euro 2008 fate over the next three months.

He has already pencilled in a trip to Fratton Park to see Campbell and goalkeeper David James in action against Manchester United on August 15.

And it would be no surprise should either man figure when McClaren announces his squad to face Germany 48 hours later.

"You can't close the door on anyone in this job," said McClaren.

"It would be silly and foolish of me to dismiss either Sol or David. I never said I would do it and I have no intention of doing it.

"Last season was a very good one for Sol and with Ben Foster being injured as well, I will certainly be going to watch Portsmouth.

"I have brought players back in the past and as long as players want to be involved with England, that is great."

McClaren was intending to look at Campbell even before Jamie Carragher dropped his retirement bombshell.

Carragher stunned McClaren by declaring his intention to quit the England scene this summer, the Liverpool man growing tired of being constantly selected for squads yet overlooked for the actual matches.

Ironically, Carragher would be ideally pleased to add to his 34 caps against Germany later this month, given the injuries afflicting the squad.

McClaren has already spoken to Carragher twice about the situation.

The England coach has extreme sympathy with the Bootle-born star and understands why he would be frustrated.

But he has managed to persuade Carragher to hang fire on a permanent stance until the pair sit down in Liverpool next week, with McClaren convinced he can talk the 29-year-old round.

He said: "Jamie Carragher is a very important player for England and a very important member of the squad."

"There is no way I want to lose him and keeping Jamie involved is my main aim at present.

"I can totally understand his thought process. I have every sympathy with players who want to play and feel they should.

"In a way, he has been quite unfortunate. There are players in every squad who can be effective in many positions, maybe sometimes to their detriment.

"I have a couple of conversations with Jamie already and I will have another one with him next week.

"Hopefully the situation can be resolved because Jamie Carragher has been a great servant to England over many years and I want that to continue."

McClaren's determination is obvious and he remains privately optimistic he can talk Carragher round.

However, speaking at the FA/McDonald's National Football Festival at Wembley Stadium, the England coach admitted the need for pragmatism meant he had to consider alternatives.

McClaren received an enthusiastic welcome from the 800 children involved in today's event, aimed at boosting the standard and availability of qualified coaching for young players in every community.

As one of the FA's valued sponsors, McDonald's has helped 9,500 new volunteer community coaches in England over the last five years.

McClaren and World Cup hero Sir Geoff Hurst were both on hand to lend support to the Wembley showpiece, the pinnacle of more than 50 festivals held across England giving free coaching to around 37,000 children.

But, as he cast an eye across the vast stadium, McClaren's mind wandered to a crucial three-month period which will determine England's Euro 2008 qualification hopes.

Vilified and ridiculed in the aftermath of March's draw in Israel and disappointing win over Andorra, McClaren's men restored some faith in June, having the better of a draw with Brazil and beating Estonia with plenty to spare.

Germany lie in wait in a fortnight, but the real action comes next month when qualification rivals Israel and Russia visit Wembley in a four-day spell.

He added: "We have put ourselves in a good position and now we are back in contention.

"I think things are looking positive. The most important thing now is to get our best players on the pitch, fill the stadium, get the fans behind us and make Wembley a fortress."