Melbourne: With key Australians players missing the Indian Premier League to preserve themselves for Ashes, questions are being raised about how seriously they are taking their preparation for the World Twenty20 Championships.

But coach Tim Nielsen has justified his players' absence in South Africa and assured the World T20 Championships was an important tournament for them, saying a side could not handle many shorter version matches, along with Tests and ODIs in a calender year.

"You can't ignore it. The game of Twenty20 cricket has taken the world by storm, hasn't it, so to be going to a world championships thinking of it as a second-rate event would be a bit silly, wouldn't it," Nielsen said.

"Just the way the international structure is, it's difficult to get enough Twenty20 cricket. I think we can only play six, which I think is the maximum any side can schedule in a season," he was quoted as saying by 'The Age' today.

Nielsen was not worried that his team was playing one-dayers against Pakistan when all the best players of the game were playing IPL in South Africa, preparing for the World T20 Championships.

"There's plenty to watch but I'm not too worried about it. I think the team that can actually adjust and adapt to the conditions and the pace of the game at international level will go the best."

"We're watching the IPL pretty closely as to how people are going about it and what they're doing but, in the end, it's a different country, different teams. Playing for your country is different to playing for a franchise," Nielsen said.

"There are only four international players in each IPL team: we're playing against 11 here. So as far as the competition goes, and playing against a quality side, I'd rather be playing international teams all the time," he added.

Brad Haddin, who will lead Australia against Pakistan, said "I think in the last World Cup guys were still feeling their way in, trying to understand Twenty20; I don't think that's the case any more. Everyone's got their head around it," he said.

Haddin believes picking Test players is the way to go. "One thing you've got to remember with Twenty20 and Test cricket, the best players in the world are still the best players in the world, whatever format of the game you play," he said.