Steve McClaren says he will not be afraid to tinker with England's system during the Euro 2008 campaign.

England have lined up in a traditional 4-4-2 formation in McClaren's first three games as boss and won them all. But, with Owen Hargreaves haven broken a leg, the manager is set to assess his tactical options along with assistant Terry Venables.

The absence of in-form Hargreaves from the mid-field could tempt McClaren to alter his formation for the matches against Macedonia, at Old Trafford on Saturday and Croatia away next week.

McClaren said: "We're thinking long and hard about what we play, now Owen is out. We might have to change it a little bit because losing a big player like that just changes the balance of the team."

Scott Parker, Michael Carrick and Phil Neville are McClaren's options if he wants a direct replacement for Hargreaves.

McClaren said: "I haven't decided who it will be, but I have something in my mind for the two games.

"Players have to be adaptable and flexible. They have to be intelligent and be able to adapt to different roles and different responsibilities.

"I'm not averse to changing systems. I was very flexible at club level, playing 4-4-2, 4-5-1, 4-3-3 or 3-5-2, to adapt to any situation and to adapt the players within that. You have to have different themes on one system, or different systems on one theme but with England, we play in a certain way - the England way.

"There's no way we can adapt and play the Brazil way or the Argentina way, we have to play to our strengths. Within that, we have to adapt and play whichever system is suited to win that game."

McClaren defines the "England way" as high-tempo football.

England will train today at Manchester United's training ground.