Clarke, 22, was the unlikely bowling weapon after removing both Sachin Tendulkar and Rahul Dravid to claim four for 42 playing only his sixth one-day international.
Australia stand top of the standings having won two of their three matches so far and have 13 points with India on eight and New Zealand on three after two games.
The talented New South Wales player is chiefly a batsman, but Ponting said he had been chosen ahead of all-rounder Ian Harvey to utilise his left-arm spin on a slow pitch.
"Michael is a young bloke who backs himself well," he told reporters after the match. "It shows the strength in our system."
"He told me he was going to get wickets today," he said. "He told me he was going to get Sachin, he did. He told me he was going to get Dravid and did that too."
TOUGH DECISION
Tendulkar was out for 68, bowled trying to make room to play a forcing shot on the off-side, and was quickly followed by Dravid, who was out reverse-sweeping for 59, as India were bowled out for 209 chasing a stiff target of 287.
Ponting said it was a tough decision to leave out Ian Harvey, especially after he took two for nine runs during the eight-wicket win over New Zealand on Wednesday.
"I didn't think I was going to get 10 overs out of Michael, but four for 42 out of 10 overs is pretty good."
Left-arm Nathan Bracken gave yet another illustration of Australia's depth in talent by claiming a career-best four for 29, taking his tally from three games in the series to 10.
The 26-year-old made the side only because of the absence through injury of the top pace trio of Glenn McGrath, Jason Gillespie and Brett Lee.
Bracken had shared seven wickets with Brad Williams to skittle New Zealand for 97 in Faridabad.
Ponting said Martyn's superb 100 on a difficult batting pitch had set up the eventual easy victory.
Martyn, 32, who was named the man of the match, was pleased with his effort made in energy-sapping humidity."
"It was very rewarding on a difficult wicket like this, having to build partnerships and with the bowlers getting a lot of turn," the Western Australia player said.
