The Indian defence crumbled under the impact of Australia's robust raids in the round-robin league encounter.
"Australia scored four times from five circle penetrations, which does not reflect well out on our defence," said Oltmans ruing that the Indian defenders did not combine well enough.
Blake Govers opened the scoring for Australia with a fifth minute penalty corner conversion, but India shot back to equalise within three minutes through Rupinder Pal Singh's low drag flick from their first penalty corner.
This was Australia's first outing in the round-robin league, while India had won their opening fixture against Japan 2-1 yesterday.
India paid dearly for allowing Australia plenty of opportunities to move inside the circle.
"I am not satisfied with the performance today. Our defenders did not gel well," said Oltmans.
Australian captain Mark Knowles too was not very pleased with the way his team played.
"The scoreline is flattering, but not our game today," said Knowles, whose team is seeking to extend their eight-title record at the Sultan Azlan Shah Cup and reclaim the title they lost to New Zealand last year.
The Black Sticks prevailed in a penalty shootout to win the title after the final against Australia ended in a draw.
"India had equal number of opportunities, but our finishing was better," said the Australian captain.
