"But, the role of an opening batsman compared to a middle-order batsman is very different. And it didn't take long to discover that when you get into challenging conditions, like they faced in the first series outside of Australia, which was in New Zealand, that opening the batting is very difficult."

"I, personally, as I said at the time, was on record saying that I didn't like changing," Hayden added. "I think it's crazy to think that you have the world's best-in-class batter in a certain position. And then you change to a completely different position. For a few reasons, I think that's crazy. Firstly, why? Such a gun in that position, such a coveted player.

"And then it also is not a great nod to the first-class set-up, which is very much in the Australian culture, been driving great results towards key roles, be that any one of the roles - wicketkeeping, batting, spinners, fast bowlers, opening batters. So the [batting positions of] one, two and three is a category which needs to be protected in my opinion. It sets up play."

"Yes, it is. It is," Hayden said. "For the first time, it doesn't feel as secure. David Warner gave a great service to Australian cricket. He gave a service that was extremely competitive, wonderfully dynamic. He really took that legacy that I'd created through the 2000s to a new level, strike rates in excess of 80 [70] and gave great momentum to the top order, which otherwise is quite a conservative, very good, but very conservative batting line-up. So I think he's an enormous loss in terms of how do you replace him.

"Clearly, they've gone in the direction of Steven Smith and thus far, whether they continue with that strategy, time will tell. And we have guys like [Cameron] Bancroft that are always in the pipeline, Matt Renshaw is in the pipeline.

"Bancroft, when you look at his form in England, has been excellent, but that's domestic cricket. It's not the Border-Gavaskar-type cricket so a bit of a few things to really prove from that engine room in Australian cricket, which has been challenged right now with David's absence."

Smith himself has said recently that he has "no idea" about his batting position for the India Tests, and that a decision would be made after Australia's white-ball tour of the UK starting September 4, where they play a T20I series against Scotland before three T20Is and five ODIs against England. "I'm happy anywhere and I'll bat wherever for the team," Smith had said. Both Cummins and Bailey have also recently hinted that Australia are likely to go with the same top six as their last four Tests to begin their Border-Gavaskar Trophy campaign.