WALLABIES captain Stirling Mortlock believes high temperatures and stifling humidity will not deter either side from playing another high-speed Bledisloe Cup match when they meet the All Blacks in Hong Kong on Saturday night.

Before the Wallabies left Sydney yesterday morning for their five-week northern hemisphere tour, Mortlock admitted the conditions in Hong Kong could be a factor - especially as only a handful of Australian squad members had played there before.

Temperatures of more than 30 degrees, rain showers, and humidity levels above 75 per cent are predicted for Hong Kong this week, and for a team which is nowhere near as match fit as the All Blacks, the conditions could result in fatigue late in the game.

But Mortlock said this was unlikely to see the Wallabies change their game tactics, adding: "No doubt we will talk about the conditions and what that will allow us to do. But if you look at the All Blacks and the Wallabies this year, both teams have been pretty positive and have played high-tempo, high-paced games. I don't think that will change too much."

That the Wallabies have had several training camps in Sydney over recent weeks might also help.

"For a few days, it was almost as if we were in England, but then it went back to being quite sunny, hot and humid," Mortlock said. "It is very hard to prepare for 95 to 99 per cent humidity, but we will have a few days preparing there before the Test."

The Hong Kong climate is one of many hurdles the Wallabies will have to deal with during what is clearly their most difficult end-of-season tour in years. While losing several crucial forwards, including Dan Vickerman, Rocky Elsom and James Horwill, has not helped, the Wallabies have been done no favours by the itinerary, which includes no easy games. After the Bledisloe Cup, the Wallabies will face an improving Italy side in Padova, before confronting, in successive weeks, England at Twickenham, France in Paris and Wales in Cardiff. They finish at Wembley against a World XV-strength Barbarians outfit.

Before some recent Wallabies spring tours, Australian players or team officials have foolishly declared they would return home unbeaten. Not this time, because Mortlock is a realist.

He also knows that just being competitive will be an achievement, especially as the Wallabies squad involves a number of newcomers and has lost so much up-front experience.

"Nothing is impossible, but certainly this tour has its challenges," he said. "The reality of this tour is that there is no easy match, or no match you would expect us to do quite well in. But that's really good, because we go away with 34 guys all itching to play Test match rugby. And every week there will be a significant mountain to climb. Even Italy a couple of years ago we found very difficult."

It's not surprising Mortlock has avoided describing the Italy Test as the easiest of the tour. The last time he was there with the Wallabies, two years ago, it proved a dramatic time.

Apart from the Wallabies struggling to beat Italy 25-18 in Rome, Mortlock's judgement was questioned when, after the Test, he was among a group of players who returned late to the team hotel. Mortlock then had a disagreement with backs coach Scott Johnson. The issue was eventually resolved, but for some days there was uncertainty over whether he would remain skipper. His captaincy has since improved remarkably. So Mortlock knows how easily one can stumble on such tours.

"From our perspective, it is all about improving our game," he said. "Hopefully, the by-product of this will be good results."