The England coach says he wants to insulate himself against an expected mass of withdrawals, which usually happens when England play a friendly.
Taylor And Milner To Be Part Of 'Huge Squad'?
Already McClaren has been informed by Liverpool boss Rafael Benitez that Steven Gerrard will not play, even though the Reds captain is apparently able to face Chelsea on Sunday despite his broken toe.
Having declared his intention to call up John Terry, Owen Hargreaves, Michael Owen and David Beckham in order to ensure they are part of the build-up, there is no guarantee any of them will play.
He says he wants to develop a 'Team England' ethos as the Euro 2008 qualifiers reach their pivotal stage, which is why the squad he announces today will be on the large side.
McClaren: "The squad I have in my mind and the team I have in my mind now could very easily change before we meet up Monday - and it will do.
"I know that. It has happened in the past and it will happen again.
"But what I want to do is establish a squad of players that we will use in the period until November.
"I do want players on the fringe but I also want to be able to stick with what we have."