Having witnessed the evolution of Twenty20 from its formative days, Australia seamer Brett Lee admits that his team's attitude towards the format has evolved over the years.

As part of the Australian team in New Zealand in 2005, Lee played in the first T20 international. To call it hit and giggle would have been to overstate the seriousness of the occasion. Donning retro uniforms and encouraged to grow their hair out or sport headbands, the two teams were there to entertain, and seemed unaware of the financial juggernaut the format would become.

"Certainly the players think that and I think the public are now starting to realise that it is the third format of the game," Lee told AAP.

"It's a very important format of the game. It used to be, reading through the press and probably from us as well in '04-05, a bit of a hit and giggle which it probably was back then because nobody knew how to take it on or what to do."

After that New Zealand tour the Australians, as their predecessors had done when one-day cricket emerged in the 1970s, took time to develop a seriousness of approach to the game, and lost the one-off T20 to England at the Rosebowl later that year having trained without taking heed of the match that evening.

"No-one knew that if you've gone for less than 32 runs off your four overs you've had an extremely good game," Lee said. "People saw you getting hit for 18-20 off your four overs and thought you were a bit expensive but as time goes on, 30 is pretty good. If you go for 40, even then it's still pretty good."

Attitudes have changed greatly in the space of six years, culminating in the launch of the T20 Big Bash League in Australia. Lee said this reflected a greater understanding of public interest in the format.

"It's about understanding your game, knowing where it can be taken to," he said. "Now that people are watching Twenty20 cricket, it's exciting. Kids come down after school, parents come down after work, they don't have to sit in the hot sun, they can watch it at night, it's got music - it's the stuff spectators love."

Nonetheless, in international terms T20 is still best served as an aperitif, and Lee applauded programmers for scheduling the two T20 internationals in Sri Lanka as a prelude to the limited overs and Test series that will follow.

"If you were to have it at the end after a Test series it probably wouldn't work as well," he said. "Definitely I think the way a series should be run, or a tour should be run, is that you start with your Twenty20s, then your one-dayers and then your Test matches. It just flows in beautifully into the longer form of the game."

As for Sri Lanka, Lee expected a fight, but one from which the tourists could emerge victorious.

"They're a very compact unit and one that's capable of beating any side around the world," Lee said. "We've had some great bouts with them where we have probably had, on paper, the better side and they've played as a team and they've played very well.

"We know that they're a very strong side and we know that they're going to come at us very hard but saying that as well, the squad we've got for Twenty20 and one-dayers is very, very strong. I'm really confident in the side we've got here to go on and take the series out."