Burley had seven withdrawals for his debut as national team coach against Croatia in March and suffered four on Monday ahead of Friday's international against the Czech Republic.

"This is a very important issue and it is something we've got to address," said Burley. "The players who are playing will naturally have a big impact on whether they stay in the side for the World Cup. It's something I've got to consider."

He added: "For me, these games are very important in getting a blend in the team for Macedonia. By the time that comes around, it will have been nine months since the European Championship campaign ended.

"Whatever happened there was nine months ago - it's about what happens in September that is important. That is something you've got to address. It's just one of the frustrations of being an international manager.

"The players who are playing have more of an advantage of being in the team than the ones who are not.

"They are in pole position and, naturally, if they perform well they've got a very good chance of staying in the side."

Key players, such as skipper Barry Ferguson, Lee McCulloch and David Weir, as well as reserve goalkeeper Allan McGregor, were absent from the original squad as Burley took into consideration Rangers' long, hard season.

Several Ibrox players also missed the 1-1 draw with Croatia and Burley added: "It's only my second game, despite taking charge in January, and I still haven't got anywhere near to seeing the squad available play for me.

"So that's a worry. For me, this is an important game. The only way you are going to get the right preparation is to get some sort of consistency in the team, so that when you come into the World Cup you have a feeling for the whole squad."