McClaren flew to the United States last week for face-to-face discussions with Beckham over his fitness and readiness to feature in next week's friendly with Germany.
Although Beckham is expected to be in the squad, McClaren will announce for the Wembley fixture on Friday, his lingering ankle injury makes any meaningful involvement against the three-time world champions extremely doubtful.
However, having performed a brave U-turn to recall Beckham to the England fold at the end of last season, McClaren is eager to keep the 32-year-old involved.
And, after chatting with Beckham, senior LA Galaxy officials Frank Yallop and Alexi Lalas, and being able to see an MLS game in the flesh, McClaren is more convinced than ever that the former Manchester United and Real Madrid star can play a major role in his side's bid to reach Euro 2008.
"It was important to see how David was and to establish a relationship with the backroom people at LA Galaxy, just as I would with any club in England," he said.
"They were very supportive. They understand where I am coming from and I understand where they are coming from.
"But the other thing I needed to do was look at the standard of the MLS.
"In doing that, you also have to understand the player involved.
"As long as he is playing competitive football, is motivated and fit, has got some goals ahead of him and the standard is okay, there would be no detriment to his performance.
"There are enough games between now and November for that to happen and as long as that continues, he will be an asset to us."
Although understandably frustrated at the delayed start to his American adventure, Beckham indicated to McClaren his enthusiasm for life in Los Angeles remains undimmed.
It is the kind of positive attitude McClaren will need in the autumn when England's Euro 2008 qualification fate is determined in five games, four of which are played on home soil.
"David is positive and bright," said McClaren.
"He is enjoying the experience but is frustrated by his injury.
"I was reassured by his determination to play for England and, if at all possible, we would like him to join us for training on Monday."
Given Beckham's lack of recent match practice, McClaren knows he needs cover in the right-sided midfield slot whether England's famed former captain flies back to London next week or not.
Shaun Wright-Phillips' return to form offers one alternative, while Blackburn's David Bentley may find out whether his decision to snub an England Under-21 call this summer has any longer lasting implications.
Bentley impressed during a B international win over Albania in May but promptly blotted his copybook by abandoning Stuart Pearce's squad ahead of the European Under-21 Championships at such a late stage it was impossible to call in a replacement.
"No-one is discounted at this present moment in time," said McClaren, without directly answering whether Bentley was eligible for selection or not.
"I have a squad in my mind but I still have one or two days in which to speak to players, managers and medical teams."
With John Terry, Owen Hargreaves and Michael Owen joining Beckham among a group of senior players expected to be fit for next month's double-header with Israel and Russia but may play no part on Wednesday, it is likely to be a mammoth squad McClaren unveils.
Joleon Lescott, Phil Jagielka and, intriugingly, Newcastle's Steven Taylor were all given specific mentions by McClaren as he assessed who impressed among the uncapped players he used against Albania and all may hope for a senior call.
One man who definitely will not be involved though is Liverpool's Jamie Carragher, who snubbed McClaren's final effort to talk him out of international retirement on Monday.
"I had a very good conversation with Jamie but unfortunately he's stayed with the decision to not be involved with us," said McClaren.
"We respect that. Jamie has been a fantastic servant for England and who knows what happens in the future."