Australia brace for Pakistan challenge

Australia captain Ricky Ponting is relishing the challenge of locking horns with Pakistan, the last team to beat the defending champions at a World Cup, when they meet on Saturday.

Australia have not lost a single game at the sport's showpiece since defeat to Pakistan at Leeds in the 1999 World Cup, a streak which the defending champions have stretched to 34 matches with a win over Canada on Wednesday.

Ponting admitted facing Pakistan is a stiff challenge and Australia's first real test in the tournament at which they are bidding to win a fourth consecutive title.

"It's always a great challenge playing against Pakistan because, as everybody knows, you're just never really sure what they're going to turn up and do on the day," said Ponting.

"They can be a very, very good side one day and, as we saw against New Zealand, they can be very, very ordinary the next. They have that sort of unpredictability about them.

"The last game they played in Colombo was against Sri Lanka and they upset them there so they'll know the conditions pretty well. So it will be our first big test," said Ponting.

The skipper admitted Australia's pace trio of Brett Lee, Shaun Tait and Mitchell Johnson had not been at their best so far.

"Against better teams and deeper batting orders, we have to make sure we don't let teams get off to that sort of start," said Ponting, speaking about Canada's brisk start against the Australians.

Ponting said he hoped frontline spinner Jason Krejza would benefit from his experience at the tournament so far.

"For someone like him to have that exposure, get 10 overs under his belt (against Canada) he should be better for the run," said Ponting.

The match comes after Pakistan paceman Shoaib Akhtar Thursday announced he would retire from international cricket after the World Cup, a decision captain Shahid Afridi believes will not affect the team.

"It's his own decision but I don't think it will affect the team. We will go into the Australia match with a positive frame of mind and we know we have the capability to beat Australia and break their unbeaten run," said Afridi.

"It is a very important match for us in the tournament and will determine our position in the group, so players know they have to win the match," said Afridi, who believes the Australians are yet to peak.

"If you look at their matches, they have shown vulnerability in both batting and bowling so we have to make sure we can exploit their weaknesses and if we can do that we can win," said Afridi.

Pakistan have won three and lost four of their seven World Cup matches against Australia, including a crucial win on their way to the 1992 World Cup triumph Down Under.

Australia have made only one change in their five matches, bringing in Michael Hussey in place of younger brother David, and are expected to play the same line-up that beat Canada by seven wickets.

Pakistan may bring in Umar Akmal, who has recovered from a finger injury, for opener Ahmed Shahzad, who has disappointed so far, as the only change. They are likely to keep rusty paceman Akhtar on the bench.