Brett Lee v Nathan Astle
Key battles: Australia v New Zealand
Lee has taken 13 wickets in eight previous matches against New Zealand. He has dismissed Astle twice.
In 20 matches against Australia, Astle has scored 672 runs at an average of 35.37, slightly above his career average of 34.84. He has hit five fifties and one century.
Lee recorded figures of 0-58 of nine overs in Australia's last match at Port Elizabeth, the narrow two-wicket victory over England in Group A.
Astle has played one previous match at St George's Park. He hit 46 in New Zealand's 20-run victory over West Indies in the Group B qualifier last month.
In 61 one-day internationals, Lee has taken 109 wickets at an average of 23.12. He boasts an impressive strike rate of 29.08.
Astle has scored 5121 of his 5540 one-day runs opening the batting. But he has been batting at three in the World Cup, where he has scored 291 runs from six innings at an average of 72.75.
Jacob Oram v Ricky Ponting
Oram has only played one previous one-dayer against Australia, taking 2-60 in New Zealand's 134-run defeat to their arch-rivals in the ICC Champions Trophy in Sri Lanka last September.
Ponting has a very good record against New Zealand. In 17 matches, he has scored 568 runs at an average of 43.69, two runs above his career average of 41.64.
Oram is enjoying a successful World Cup. He has taken 12 wickets at an average of 18.92 in six matches in South Africa.
St George's Park is one of Ponting's favourite grounds. He shared a record 183-run partnership with Darren Lehmann in Australia's three-wicket victory over South Africa in April 2002.
Oram took 2-60 in New Zealand's 20-run Group B victory over West Indies at Port Elizabeth last month.
Although Ponting has never been dismissed by Jacob Oram, he has been out to Shane Bond on five different occasions. Shoaib Akhtar, Shahid Afridi and Lance Klusener have also dismissed him five times.
The BBC is not responsible for the content of external internet sites