Beaten inside four days in the series opener in Brisbane, England succumbed to their second successive defeat in Adelaide despite Jos Buttler's dogged resistance with the bat.

"The Ashes are on the line here, if that is not motivation, I don't know what is," Root said after his team's 275-run defeat in the day-night test.

Buttler's 26 runs from 207 balls delayed Australia's victory charge for a while and Root said that should be the blueprint for the remaining matches in Melbourne, Sydney and Hobart.

"Ultimately that is the attitude and the mentality we have to harness over the next five days," Root said.

"I am extremely proud of the way the guys fought today, that attitude and desire that's how we need to go about a whole test match.

"I thought Jos's innings was outstanding on that pitch. He should have gained a lot more confidence from this."

Asked whether he had picked the wrong team for Adelaide, Root said his bowlers should have bowled a fuller length with the pink ball.

"We need to be braver and get the ball up there," he said.

"The most disappointing thing for me is the amount of no-balls we keep bowling. We don't think Australia are that much better than us in these conditions. We are better than we have played."

Belief was essential to trying to get back into the series, he said. 

"We need to believe, we need to keep learning, we need to learn faster. We can't make the same mistake we have done so far. We need to have the same attitude as today," Root added.

"If we do that, I am convinced, we have what it takes but we cannot makes mistakes. We need partnerships and big contributions."

Root was deeply disappointed with himself for getting out last ball to Mitchell Starc on Sunday night after being hit in the groin a few minutes before.

He was also injured in the same area in the early morning practice.

"I was gutted last night. It was a tough day yesterday. I was very cross with myself. I should have been able to stay on and put the pads on today and lead by example," he said.

(Editing by Amlan Chakraborty and Christian Radnedge)

By Richard Evans