When Australia's Michael Clarke took part in the first ever international Twenty20 match, against New Zealand five years ago, the emphasis was very much on "fun".

New Zealand players dressed up in retro kit, with some sporting hairstyles more associated with the 1960s and 70s.

Australia captain Ricky Ponting made 98 as his side won by 44 runs in Auckland but questioned whether the "novelty” of 1Wenty20 would endure.

The emphasis in Australian cricket remained very much on Tests and one-day internationals so that the side's defeat by outsiders Zimbabwe at the inaugural World Twenty20 in Cape Town was brushed aside by Australian fans.

Australia was well beaten by India in the 2007 semifinal and at last year's edition in England, they were knocked out in three days after defeats by the West Indies and Sri Lanka.

But that exit was overshadowed by the context of an Ashes tour and when Ponting announced he was retiring from international Twenty20, there was a general sense of relief the star batsman would still be available to play 'proper' cricket for his country.

However, with Clarke now their captain in this format, Australia began their 2010 World Twenty20 campaign with a 34-run win over defending champions Pakistan here on Sunday.

And top order batsman Clarke said the advent of the tournament had led to a change in Australian attitudes towardsT\iventy20.

"1 think now there's a world championship, that plays a big part," he said.

"When I played in my first T\venty20 match, we played against New Zealand and they were growing moustaches, not cutting their hair and wearing 1960s outfits to play the games.

"Everybody is taking the game a lot more seriously now and in tournaments like this, you want to do well. We haven't done as well as we would like but we've started well.”

Australia complete their group programme against Bangladesh in Barbados on Wednesday and, having seen his team lose to Zimbabwe in a warm-up fixture, Clarke was adamant he would not be underestimating Bangladesh.

"It just shows in this form of the game, you have to be at your best, it doesn't matter who you are playing against," he said.

"We certainly won't be taking Bangladesh lightly. They've got some wonderful Twenty20 players who are very aggressive with the bat.”