Damien Martyn top-scored with 73 not out to guide world champions Australia into the Champions Trophy semi-finals on Sunday with a convincing six-wicket victory over hosts India.

Australian skipper Ricky Ponting struck 58 and all rounder Shane Watson hammered a 46-ball 50 to spur their team to 252 for four with 4.2 overs to spare after restricting India to 249 for eight in the must-win final Group A clash.

Indian opener Virender Sehwag made 65 and skipper Rahul Dravid, who elected to bat, struck 52 before the Australian pacemen, led by Glenn McGrath, pegged them down on a batting pitch.

McGrath, Brett Lee and Nathan Bracken took two wickets apiece.

Australia topped Group A and face New Zealand in the first semi-final on Wednesday in Mohali. Defending champions West Indies take on South Africa in the second semi-final in Jaipur the next day.