Ponting back in training

Melbourne - Australian captain Ricky Ponting has resumed training as he attempts to prove his fitness ahead of this month's Cricket World Cup.

However, the makeup of Australia's final squad for the series continues to be surrounded by uncertainty, with reserve spinner Xavier Doherty battling a back problem and Mike Hussey struggling with a hamstring injury.

Ponting has not played since the fourth Test against England at the MCG in late December, but returned to the nets on Tuesday.

The 36-year-old damaged the little finger on his left hand in the third Test at the WACA, but aggravated the injury in Melbourne and needed surgery.

Team physiotherapist Alex Kountouris said the Australian captain would increase his workload over the coming days.

"Ricky Ponting had his first training session yesterday since having finger surgery after the Melbourne Test match," Kountouris said on Wednesday, as Australia faced England in the sixth one-day match in Sydney.

"As part of his recovery this was a restricted session and he is expected to increase his training intensity in the lead up to the ICC Cricket World Cup.

"He has had no adverse effect from yesterday's session and has trained again today during Australia's batting innings."

Meanwhile Doherty, who was first in line to replace injured fellow spinner Nathan Hauritz, has been ruled out of the last two games of the ODI series.

"Xavier Doherty developed some back pain during the one-day game in Adelaide on Australia Day and did not train in Brisbane which allowed his symptoms to improve," he said.

"He attempted some light training yesterday in Sydney and his back was again painful. His return to cricket will be determined by monitoring his recovery over the next week."

Veteran batsman Mike Hussey is also struggling to be fit for the World Cup after a serious hamstring injury that required surgery.

His likely replacement, the injury-plagued Shaun Marsh, has also been struck down by a hamstring strain suffered at the Gabba on Sunday.