George Burley is well aware that his players have already come through a long, hard season with their clubs.

But the Scotland manager was keen to remind them that the international campaign is just beginning and he needs a massive effort in forthcoming friendlies ahead of the World Cup qualifiers in September.

First up is the Czech Republic on Friday, before Northern Ireland come calling at Hampden in August.

And, as far as Burley is concerned, these matches will play a crucial part in his preparations for his first qualification campaign.

"It will be a huge challenge," he said of the impending trip to Prague.

"It's my second game and we have one more friendly after this one before the World Cup campaign so it's very important.

"It's the end of the season for the club sides but, for international level, these are the build-up games.

"There are a lot of top teams in Europe, like the Czech Republic, preparing for the European Championships and their focus is on that.

"Our focus is on the World Cup qualifiers in September. So it's an important game in terms of preparation for our first game against Macedonia."

Skipper Barry Ferguson, David Weir, Lee McCulloch and Allan McGregor were all absent from Burley's squad announcement earlier this month as he took into consideration the mammoth season they have been through with Rangers.

Asked whether he has concerns that fatigue will be a factor for those who will be involved this week, he said: "There are so few opportunities in the international calendar to play games.

"England have two, Wales are playing three and the Republic of Ireland have had a week's training camp and will play two more games. We're trying to get things right for the World Cup.

"If you just ignore and not play a game, I don't think that would be right. If we had been in the Euros, what would we be saying now? That we're too tired to play in them?

"It's important and there are a number of players who will be given an opportunity, and maybe debuts, against a team ranked sixth in the world.

"It will be a very difficult game but it's one we will be looking to perform well in and try to get something out of."

Alan Hutton, James McFadden and Rangers duo Steven Whittaker and Kevin Thomson have withdrawn from the squad on Monday through injury, with Motherwell's David Clarkson a late call-up.

But Burley remained upbeat, insisting it would an opportunity for others to stake a claim for a place in his plans ahead of the qualifiers.

He said: "We had seven call-offs for the last game against Croatia and I thought it was a terrific game. I thought the team performed very well.

"We have got call-offs for the Czech Republic but it gives other people opportunities.

"The lads who played against Croatia took the opportunity and we would be looking for the same against the Czech Republic.

"If you take your chance, you have a better chance of staying in the team for the World Cup games."

And he has no qualms about giving youth a chance, adding: "You are always looking to add young blood. In the squad we have 16 players who are 26 and under.

"We've got a good nucleus of players who are still maturing, still improving, and that can only be a good thing because the World Cup [qualifying campaign] lasts for two years and hopefully we can keep developing talent and giving them the opportunity in the full squad."

A positive approach in his debut earned Burley a 1-1 draw with Croatia back in March and he has promised more of the same against the Czech Republic.

"We will try to be positive, although we know it's going to be a difficult game," he said.

"I've got a group of players who are very hungry, they want to play for their country, and they are very passionate so we won't be going there just to roll over.

"We will be going there to try to perform well and get the right build-up for the World Cup qualifiers."

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