Australian bowler Pat Cummins reaches for the ball on the second day of the fourth Test cricket match between South Africa and Australia won by South Africa at Wanderers cricket ground on March 31, 2018 in Johannesburg, South Africa. / AFP PHOTO / GIANLUIGI GUERCIA (Photo credit should read GIANLUIGI GUERCIA/AFP/Getty Images)

Australian captain Pat Cummins has suggested his batsmen "went away from their methods" during a dramatic collapse in Delhi.

Australia lost 9 wickets in an hour and a half to capitulate from the position of 2 for 85 to be all out for 113. Australia lost four wickets with the score stranded on 95, with India knocking off the 115-run target for the loss of just four wickets.

The session of play in which Australia fell apart saw six batsmen dismissed attempting to sweep the ball, and followed a dismal batting performance in the Nagpur Test, which Australia lost by an innings.

The second defeat ensures the Border-Gavaskar trophy will be retained by the Indians, who last won the trophy in Australia and only needed to draw the four-Test series to ensure it would stay in their grasp.

The second innings collapse for Australia followed a 114-run partnership between Axar Patel and Tavichandran Aswhin that saved the Indian first innings from 7 for 139, taking it to 8 for 253 - India ultimately were just a single run behind on first innings after Australia managed to make 263 on the opening day of play.

Cummins, speaking after the match, said Australia's batsmen had gone away from their plans in facilitating the soft collapse.

"I thought they bowled really well, it's not easy out there, but perhaps some guys went away from their methods," said Cummins, himself a victim of an attempted slog-sweep from his first ball on day three.

"Each batter has their own way to go about it. I don't think there's any one-size-fits-all rule.

"Unfortunately, quite a few of us got out with kind of cross-batted shots which might not be our preferred method.

"A few of the lessons we learned well from last week (served us) well in the first innings at times, (but) probably at times just overplayed that in the second.

"Nagpur maybe (we) underplayed it. We probably overplayed it here at times in the second innings.

"You've got to find a way to try and put pressure back on the bowlers, they're really, really good bowlers, especially in these conditions. Probably just at times maybe just overplayed it.

"Two big things we talk about is the tempo of the game and the method. Maybe at times a little bit too high tempo.

"I'd rather be high tempo than low tempo though, to be honest, if those wickets are being difficult.

"But maybe the method went a little bit away from what we planned to do at times."

Cheteshwar Pujara, who was out cheaply in India's first innings to Nathan Lyon for a duck, before making 31 not out in the second innings as India cruised to victory, explained that sweeping on the turning Delhi track wasn't the ideal shot to play.

"If you look at this pitch, it's not an ideal shot to play because there's low bounce," Pujara said.

"If there's enough bounce I might play that. But it is difficult … if you can move your feet, get close to the ball, or play on the back foot, then it's better on turning tracks.

"I've always done that throughout my career and it's helped me a lot."

Australia will now attempt to regroup ahead of the third Test, which starts on March 1 in Indore, and will likely see the returns of Mitchell Starc and Cameron Green, who have missed the first two Tests after both suffering finger injuries during the final Test of the home summer against South Africa in Sydney.